https://www.heatjac.com/knowledgeThe HEATJAC knowledge hub covers how the body loses heat, heating and cooling technologies, and staying warm at work, outdoors and with cold sensitivity.en-usSat, 10 Oct 2026 02:37:42 GMThttps://www.heatjac.com/knowledge/heated-scrub-jacket-buyers-guidehttps://www.heatjac.com/knowledge/heated-scrub-jacket-buyers-guideSat, 10 Oct 2026 02:37:41 GMTBefore buying a heated scrub jacket, check five things: whether your facility's attire policy allows a personal or battery-powered layer in your area, where the battery and cord sit, whether the garment can be laundered the way policy requires, whether it fits under a gown or lead apron, and whether a passive heat-reflective or insulated layer would do the job with fewer approvals.HealthcareBuyer's Guidehttps://www.heatjac.com/knowledge/hypothermia-blankets-comparedhttps://www.heatjac.com/knowledge/hypothermia-blankets-comparedSat, 10 Oct 2026 02:37:33 GMTActive systems that add heat, such as the HPMK and Ready-Heat blankets, generally lost the least heat in fluid-model lab studies, and the Blizzard insulated blanket was the best passive option in the Army and UK studies. Plain space blankets and single wool blankets ranked lowest. The military Joint Trauma System recommends an insulated wrap plus an active heat source, kept off bare skin.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/why-batteries-die-in-the-coldhttps://www.heatjac.com/knowledge/why-batteries-die-in-the-coldSat, 10 Oct 2026 02:37:28 GMTBatteries die in the cold because low temperatures slow the chemistry inside lithium-ion cells. The electrolyte thickens, internal resistance rises, and the cell cannot deliver power fast enough, so devices drain quickly or shut off. Apple and Samsung design their phones for 32 to 95 °F (0 to 35 °C). The loss is usually temporary and returns once the battery warms.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/hand-warmers-for-raynaudshttps://www.heatjac.com/knowledge/hand-warmers-for-raynaudsFri, 09 Oct 2026 20:42:53 GMTThe best hand warmers for Raynaud's give gentle, steady heat you can start before your fingers get cold: rechargeable warmers with adjustable settings, air-activated packets inside mittens, or click warmers for a quick boost. The National Institutes of Health lists hand warmers and heated gloves among Raynaud's self-care steps. Pair them with a warm core, and never press a hot warmer against numb skin.Technology and GearHand and Body Warmershttps://www.heatjac.com/knowledge/toe-warmers-body-warmers-which-goes-wherehttps://www.heatjac.com/knowledge/toe-warmers-body-warmers-which-goes-whereFri, 09 Oct 2026 20:42:50 GMTDisposable toe warmers are rated to last up to 7 to 8 hours, and stick-on body warmers up to 12 to 18 hours. Toe warmers are built to run cooler, around 102 to 113 °F (39 to 45 °C), because they sit inside a boot against the foot. Each type is shaped for one place, so match the warmer to the spot.Technology and GearHand and Body Warmershttps://www.heatjac.com/knowledge/rechargeable-vs-disposable-hand-warmershttps://www.heatjac.com/knowledge/rechargeable-vs-disposable-hand-warmersFri, 09 Oct 2026 20:42:47 GMTNeither wins everywhere. Disposable air-activated warmers run longer per use, often rated at up to 10 hours, need no charging and suit occasional use. Rechargeable warmers are often rated for up to about 6 hours per charge on low, offer adjustable heat and cost less over many uses, but they carry lithium-ion battery risks and follow FAA battery rules when you fly.Technology and GearHand and Body Warmershttps://www.heatjac.com/knowledge/reusable-click-hand-warmers-how-they-workhttps://www.heatjac.com/knowledge/reusable-click-hand-warmers-how-they-workFri, 09 Oct 2026 20:42:44 GMTReusable click hand warmers hold a supersaturated solution of sodium acetate in water. Flexing the small metal disc starts crystallization, and as the liquid turns solid it releases stored heat, reaching about 129 °F (54 °C). The heat lasts minutes rather than hours. Boiling the pad in water redissolves the crystals so it is ready to use again.Technology and GearHand and Body Warmershttps://www.heatjac.com/knowledge/can-you-reuse-hand-warmershttps://www.heatjac.com/knowledge/can-you-reuse-hand-warmersFri, 09 Oct 2026 20:42:41 GMTNot fully. A disposable air-activated hand warmer cannot be recharged once its iron has oxidized, but you can pause a partly used one. Seal it in an airtight zip-top or freezer bag with the air pressed out, and the reaction slows to a stop. Open the bag later and it heats again, using only the energy that was left.Technology and GearHand and Body Warmershttps://www.heatjac.com/knowledge/where-to-put-hand-warmershttps://www.heatjac.com/knowledge/where-to-put-hand-warmersFri, 09 Oct 2026 20:42:38 GMTPut warmers in two places: on your core and where you feel cold. An adhesive body warmer stuck to your base layer over the upper back or chest keeps blood flowing to your hands, while hand warmers go in mittens, glove pockets or jacket pockets. In a Canadian defense research study at -13 °F (-25 °C), heating the torso kept fingers more dexterous than heating the hands directly.Technology and GearHand and Body Warmershttps://www.heatjac.com/knowledge/medications-that-make-you-feel-coldhttps://www.heatjac.com/knowledge/medications-that-make-you-feel-coldFri, 09 Oct 2026 20:42:35 GMTSeveral medicine classes can make you feel cold. Beta blockers, ADHD stimulants, triptans and ergot drugs can narrow blood flow to the fingers and toes; oxaliplatin causes nerve symptoms triggered by cold; and antipsychotics can occasionally lower core body temperature. A 2016 review identified 12 drug classes linked to Raynaud's phenomenon. Never stop a medicine on your own; talk to your prescriber first.Everyday Life and HealthMedications and Temperaturehttps://www.heatjac.com/knowledge/hypothyroidism-feeling-coldhttps://www.heatjac.com/knowledge/hypothyroidism-feeling-coldFri, 09 Oct 2026 20:42:33 GMTHypothyroidism makes you feel cold because low thyroid hormone slows the body's metabolism, so it produces less heat at rest and less extra heat when you are chilled. In a Swiss study, restoring normal thyroid levels raised the body's heat response to mild cold by about 102%. Most people warm up with proper treatment, but persistent cold deserves a talk with your clinician.Everyday Life and HealthMedications and Temperaturehttps://www.heatjac.com/knowledge/adhd-stimulants-cold-handshttps://www.heatjac.com/knowledge/adhd-stimulants-cold-handsFri, 09 Oct 2026 20:42:30 GMTYes, ADHD stimulants can cause cold hands. US labels for amphetamine (Adderall XR) and methylphenidate (Concerta) warn that these medicines are associated with peripheral vasculopathy, including Raynaud's phenomenon: fingers or toes that feel numb, cool or painful and turn pale, blue, then red. Symptoms are usually mild and intermittent. Tell the prescriber, and do not change the dose on your own.Everyday Life and HealthMedications and Temperaturehttps://www.heatjac.com/knowledge/beta-blockers-cold-hands-feethttps://www.heatjac.com/knowledge/beta-blockers-cold-hands-feetFri, 09 Oct 2026 20:42:27 GMTYes. Cold hands and feet are a recognized side effect of beta blockers. The NHS lists them among common side effects, and US labels for metoprolol and propranolol list cold extremities or arterial insufficiency of the Raynaud type. Beta blockers lower the heart's output and can block signals that widen small blood vessels. Never stop one suddenly; talk to your prescriber.Everyday Life and HealthMedications and Temperaturehttps://www.heatjac.com/knowledge/feeling-cold-on-mounjaro-zepboundhttps://www.heatjac.com/knowledge/feeling-cold-on-mounjaro-zepboundFri, 09 Oct 2026 20:42:24 GMTFeeling cold is not a listed side effect of Zepbound or Mounjaro. Neither US prescribing information lists chills, feeling cold or cold intolerance. The likely reasons are indirect: tirzepatide decreases calorie intake, and weight lost is mostly fat, which insulates. Listed effects such as fatigue, dizziness and low blood pressure can also feel like a chill. Persistent cold deserves a talk with your clinician.Everyday Life and HealthMedications and Temperaturehttps://www.heatjac.com/knowledge/why-losing-weight-makes-you-coldhttps://www.heatjac.com/knowledge/why-losing-weight-makes-you-coldFri, 09 Oct 2026 20:42:21 GMTLosing weight can make you feel colder because you have less body fat to insulate you and because eating less turns down heat production. In a six-month JAMA trial, people on calorie restriction had lower core body temperature and burned about 135 fewer calories a day while sedentary. Cold that is extreme, long-lasting or comes with unplanned weight loss deserves a clinician's check.Everyday Life and HealthMedications and Temperaturehttps://www.heatjac.com/knowledge/shivering-after-c-section-childbirthhttps://www.heatjac.com/knowledge/shivering-after-c-section-childbirthFri, 09 Oct 2026 20:42:18 GMTShivering after a C-section or childbirth is very common and usually harmless. Research reviews report that up to 85% of people shiver after spinal anesthesia for a cesarean, and many shake after a vaginal birth too. It usually settles within an hour or two with blankets and warming. Shaking with a fever of 100.4 °F (38 °C) or heavy bleeding needs prompt attention.HealthcareSurgery and Recoveryhttps://www.heatjac.com/knowledge/feeling-cold-during-blood-transfusionhttps://www.heatjac.com/knowledge/feeling-cold-during-blood-transfusionFri, 09 Oct 2026 20:42:15 GMTFeeling cold during a blood transfusion can come from the blood itself, since red cells are refrigerated at about 43 °F (6 °C), or from a reaction. Chills with a fever are one of the most common reactions, occurring in about 1% of transfusions. Because chills can also signal a rarer, serious reaction, tell your nurse the moment you feel chilled or shaky.HealthcareSurgery and Recoveryhttps://www.heatjac.com/knowledge/why-hospitals-are-coldhttps://www.heatjac.com/knowledge/why-hospitals-are-coldFri, 09 Oct 2026 20:42:12 GMTHospitals feel cold mostly because of the person, not the thermostat. CDC infection-control guidance lists a design range of 70 to 75 °F (21 to 24 °C) for patient rooms, an ordinary indoor range. Patients feel colder because they lie still in a thin gown, may be ill or fasting, and may receive room-temperature IV fluids. Imaging and equipment rooms can run cooler.HealthcareSurgery and Recoveryhttps://www.heatjac.com/knowledge/staying-warm-recovering-after-surgeryhttps://www.heatjac.com/knowledge/staying-warm-recovering-after-surgeryFri, 09 Oct 2026 20:42:09 GMTFeeling cold for weeks after surgery is common and usually reflects recovery itself: blood loss and anemia, eating less, moving less, poor sleep and some medicines all reduce the heat your body makes. In an Australian and New Zealand study of major abdominal surgery, 59% of patients checked before discharge were anemic. Cold with fever, wound changes or breathlessness needs a clinician.HealthcareSurgery and Recoveryhttps://www.heatjac.com/knowledge/what-to-bring-to-hospital-to-stay-warmhttps://www.heatjac.com/knowledge/what-to-bring-to-hospital-to-stay-warmFri, 09 Oct 2026 20:42:07 GMTTo stay warm in the hospital, pack layers you control: a robe, a front-opening sweater or zip top that clears IV lines and monitors, warm socks, slippers with non-slip soles and a firm fit, and a soft hat. Leave heating pads and electric blankets at home; many hospitals do not allow them, and nurses can bring warmed blankets instead.HealthcareSurgery and Recoveryhttps://www.heatjac.com/knowledge/chills-after-surgery-no-feverhttps://www.heatjac.com/knowledge/chills-after-surgery-no-feverFri, 09 Oct 2026 20:42:04 GMTChills after surgery without a fever are common, especially in the first day or two, when anesthesia, inflammation, pain, a cool room and blood loss can all make you shiver. Chills can also come just before a fever rises, so recheck your temperature. Call your surgeon for a reading above 100.4 °F (38 °C), shaking chills, or chills that start several days after surgery.HealthcareSurgery and Recoveryhttps://www.heatjac.com/knowledge/why-iv-fluids-make-you-coldhttps://www.heatjac.com/knowledge/why-iv-fluids-make-you-coldFri, 09 Oct 2026 20:41:29 GMTIV fluids make you feel cold because they are usually given at room temperature, well below your body's average of 98.6 °F (37 °C), so your body has to warm every milliliter. Anesthesia teaching material estimates that each liter of room-temperature fluid lowers average body temperature by about 0.45 °F (0.25 °C). The arm with the IV usually feels coldest first.HealthcareSurgery and Recoveryhttps://www.heatjac.com/knowledge/recommended-room-temperatureshttps://www.heatjac.com/knowledge/recommended-room-temperaturesTue, 29 Sep 2026 05:47:00 GMTThere is no single ideal room temperature; the right target depends on the setting. The World Health Organization proposes at least 18°C (64°F) in homes during cold seasons. OSHA recommends 68 to 76°F (20 to 24°C) for offices, the NHS advises 16 to 20°C for a baby's room, and refrigerators should stay at 40°F (4°C) or below.Everyday Life and HealthTools and Datahttps://www.heatjac.com/knowledge/cold-weather-numbershttps://www.heatjac.com/knowledge/cold-weather-numbersTue, 29 Sep 2026 05:46:00 GMTHypothermia is a core body temperature below 35°C (95°F): mild from 32 to 35°C (90 to 95°F), moderate from 28 to 32°C (82 to 90°F) and severe below 28°C (82°F). Skin freezes in air below about -3°C (26.6°F), and at wind chills of -28 or colder, exposed skin can freeze in 30 minutes or less.Science of WarmthTools and Datahttps://www.heatjac.com/knowledge/clo-values-clothing-tablehttps://www.heatjac.com/knowledge/clo-values-clothing-tableTue, 29 Sep 2026 05:45:00 GMTOne clo equals 0.155 m²·K/W of clothing insulation. In ASHRAE Standard 55-2013, trousers with a short-sleeve shirt rate 0.57 clo, trousers, long-sleeve shirt and suit jacket 0.96 clo, and insulated coveralls over thermal underwear 1.37 clo. To estimate any outfit, add the garment values; ISO 9920 refines that sum as 0.161 + 0.835 × the total.Science of WarmthTools and Datahttps://www.heatjac.com/knowledge/thermal-comfort-glossaryhttps://www.heatjac.com/knowledge/thermal-comfort-glossaryTue, 29 Sep 2026 05:44:00 GMTThermal comfort is the condition of mind that expresses satisfaction with the thermal environment, as ASHRAE Standard 55 defines it. This glossary defines 80 terms across body heat, heat transfer, clothing, weather indexes, standards and clinical warming. The two core units: 1 clo of clothing insulation equals 0.155 m²·°C/W, and 1 met of metabolic heat equals 58.2 W/m².Science of WarmthTools and Datahttps://www.heatjac.com/knowledge/heat-illness-work-statisticshttps://www.heatjac.com/knowledge/heat-illness-work-statisticsTue, 29 Sep 2026 05:43:00 GMTIn 2024, 48 US workers died from exposure to environmental heat, according to the Bureau of Labor Statistics Census of Fatal Occupational Injuries, compared with 43 in 2022 and 36 in 2021. From 1992 to 2022, 986 workers died from heat exposure on the job, an average of 34 a year, and construction accounted for about 34 percent of those deaths.Heat and CoolingTools and Datahttps://www.heatjac.com/knowledge/raynauds-statisticshttps://www.heatjac.com/knowledge/raynauds-statisticsTue, 29 Sep 2026 05:42:00 GMTRaynaud's is common. The only systematic review of general population studies (Garner and colleagues, BMJ Open, 2015; 33 studies, 33,733 people) put the pooled prevalence of primary Raynaud's at 4.85%, with 5.74% in women and 4.12% in men. Most cases are primary, while about 95% of people with systemic sclerosis have Raynaud's.Everyday Life and HealthTools and Datahttps://www.heatjac.com/knowledge/perioperative-hypothermia-statisticshttps://www.heatjac.com/knowledge/perioperative-hypothermia-statisticsTue, 29 Sep 2026 05:41:00 GMTPerioperative hypothermia, a core temperature below 36.0°C under NICE CG65, is common. In a 2015 Anesthesiology study of nearly 59,000 patients warmed with forced air, 64% fell below 36°C in the first hour. A 2017 national study across 28 Chinese hospitals found 44.3%. Rates vary widely with definition, setting and how actively patients are warmed.HealthcareTools and Datahttps://www.heatjac.com/knowledge/cold-stress-work-injury-statisticshttps://www.heatjac.com/knowledge/cold-stress-work-injury-statisticsTue, 29 Sep 2026 05:40:00 GMTFederal data record relatively few direct cold injuries at work. In 2020, private employers reported 190 cases of exposure to environmental cold, such as frostbite or hypothermia, that caused at least one day away from work, compared with 1,940 for environmental heat. Winter's larger toll is indirect: in 2014, 42,480 days-away cases involved ice, sleet or snow.Work and DutyTools and Datahttps://www.heatjac.com/knowledge/cold-related-deaths-statisticshttps://www.heatjac.com/knowledge/cold-related-deaths-statisticsTue, 29 Sep 2026 05:39:00 GMTIn 2023, 1,024 deaths in the United States were attributed to excessive cold or hypothermia, according to CDC's National Center for Health Statistics, with January the peak month. In Canada, Statistics Canada vital statistics record 1,678 deaths from exposure to excessive natural cold from 2011 to 2023, an average of 129 a year. Men and older adults account for most deaths.Everyday Life and HealthTools and Datahttps://www.heatjac.com/knowledge/what-to-wear-by-temperaturehttps://www.heatjac.com/knowledge/what-to-wear-by-temperatureTue, 29 Sep 2026 05:38:00 GMTDress in three loose layers: a wicking base layer (wool or synthetic, not cotton), an insulating middle layer, and an outer layer that blocks wind and water. Add a hat and gloves around 40°F (4°C) and switch to mittens near 0°F (-18°C). Add a windproof shell when windy, dress warmer when standing still, and about 20°F lighter when running.Everyday Life and HealthTools and Datahttps://www.heatjac.com/knowledge/cold-water-survival-timehttps://www.heatjac.com/knowledge/cold-water-survival-timeTue, 29 Sep 2026 05:37:00 GMTSurvival time in cold water is usually decided in the first minutes, not hours. Cold shock peaks in water between 10 and 15°C (50 to 59°F) and can cause drowning within seconds, and arms can fail within minutes. Hypothermia takes at least 30 minutes to develop in adults, even in ice-cold water. Wearing a life jacket is the single biggest factor.Everyday Life and HealthTools and Datahttps://www.heatjac.com/knowledge/cold-work-warm-up-schedulehttps://www.heatjac.com/knowledge/cold-work-warm-up-scheduleTue, 29 Sep 2026 05:36:00 GMTEnter air temperature and wind speed, and the tool returns the ACGIH maximum work period and number of 10-minute warm-up breaks for a 4-hour shift of moderate to heavy work. Extra breaks start at -26°C (-15°F) with a 16 km/h (10 mph) wind; at -43°C (-45°F) and below, non-emergency work should cease in any wind.Work and DutyTools and Datahttps://www.heatjac.com/knowledge/wind-chill-frostbite-calculatorhttps://www.heatjac.com/knowledge/wind-chill-frostbite-calculatorTue, 29 Sep 2026 05:35:00 GMTEnter air temperature and wind speed, and the calculator applies the 2001 wind chill index used by the US National Weather Service and Environment Canada. At 0°F with a 15 mph wind, wind chill is -19°F (about -29°C). Environment Canada rates wind chills from -28 to -39 as high risk: exposed skin can freeze in 10 to 30 minutes.Science of WarmthTools and Datahttps://www.heatjac.com/knowledge/crossing-guard-traffic-post-coldhttps://www.heatjac.com/knowledge/crossing-guard-traffic-post-coldTue, 29 Sep 2026 05:10:00 GMTFor crossing guard duty in winter, wear a thin wicking base layer, an insulating mid layer and a windproof coat, then put a correctly sized high-visibility garment on top so nothing covers it. Add a hat that covers the ears, gloves that still grip a stop paddle, and insulated waterproof boots, and step off the post to warm up when you can.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/farm-livestock-winter-workhttps://www.heatjac.com/knowledge/farm-livestock-winter-workTue, 29 Sep 2026 05:09:00 GMTWinter farm work is risky because cold, wind, wet chores and cold water combine, often alone and at night. Stay safe by dressing in three layers with spare dry gloves and socks, keeping walkways sanded, never running tractors or fuel heaters in closed buildings without ventilation and a working CO alarm, telling someone where you are, and knowing the signs of hypothermia and frostbite.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/mail-carrier-delivery-driver-coldhttps://www.heatjac.com/knowledge/mail-carrier-delivery-driver-coldTue, 29 Sep 2026 05:08:00 GMTTo stay warm as a mail carrier or delivery driver, dress for the walk rather than the cab: thin, loose layers you can open between stops, a dry base layer that moves sweat away, a hat, waterproof insulated boots with good tread, and gloves you can work in. Change damp layers early, and never idle the vehicle in an enclosed space.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/cold-after-surgery-shiveringhttps://www.heatjac.com/knowledge/cold-after-surgery-shiveringTue, 29 Sep 2026 05:07:00 GMTFeeling cold after surgery is common. Anesthesia blunts the body's temperature control, heat shifts from the core to the skin within the first hour, and operating rooms are cool, so unwarmed patients typically lose 1 to 2°C of core temperature. Shivering after anesthesia is uncomfortable but usually not dangerous, and it normally settles within 20 to 30 minutes with warming.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/keeping-a-bedbound-person-warmhttps://www.heatjac.com/knowledge/keeping-a-bedbound-person-warmTue, 29 Sep 2026 05:06:00 GMTTo keep a bedridden person warm, hold in their own body heat rather than adding hot devices. Keep the room at least 68 to 70°F, use several light layers of breathable bedding, cover the head, neck and feet, keep skin and sheets dry, and uncover only one area at a time when repositioning. Use heating devices only to prewarm the bed, never against skin.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/keeping-a-person-with-dementia-warmhttps://www.heatjac.com/knowledge/keeping-a-person-with-dementia-warmTue, 29 Sep 2026 05:05:00 GMTA person with dementia may not notice or say they are cold, may forget to dress for the weather, and may wander outdoors. Keep their main rooms at 64 to 70°F or warmer, dress them in thin layers, check warmth at the back of the neck, supervise any heating device closely, plan for winter wandering and learn the signs of hypothermia.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/cold-arm-or-leg-after-strokehttps://www.heatjac.com/knowledge/cold-arm-or-leg-after-strokeTue, 29 Sep 2026 05:04:00 GMTAn arm or leg on the side affected by a stroke often feels cold, and may measure colder, because the stroke disrupts the nerve signals that control blood vessel tone in that limb, reducing skin blood flow. Sensation can also change, so the limb may feel cold yet not sense heat. Warm it gently with layers, and never put direct heat on it.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/does-cold-weather-make-joint-pain-worsehttps://www.heatjac.com/knowledge/does-cold-weather-make-joint-pain-worseTue, 29 Sep 2026 05:03:00 GMTPartly. Many people with arthritis or fibromyalgia say cold, damp weather makes their pain worse, and some studies find a real but modest link with humidity, wind and low air pressure. Temperature itself shows little consistent effect, and several large studies found no link at all. Your own pattern matters more than the average, and staying warm and active can help comfort.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/pots-dysautonomia-coldhttps://www.heatjac.com/knowledge/pots-dysautonomia-coldTue, 29 Sep 2026 05:02:00 GMTYes, POTS can cause cold hands and cold feet, because the autonomic nervous system that controls blood vessels and body temperature does not adjust normally. Blood pools in the lower body when you stand, so less warm blood reaches the hands and feet, which can look pale or purple. Many people also swing between hot and cold, so gentle, adjustable warmth works best.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/parkinsons-body-temperaturehttps://www.heatjac.com/knowledge/parkinsons-body-temperatureTue, 29 Sep 2026 05:01:00 GMTFeeling cold is common with Parkinson's because the disease affects the autonomic nervous system, which controls sweating, blood vessel tone and other parts of temperature regulation. Many people notice cold hands, feet or legs, or feel too cold or too hot when others feel fine. Steady layering, a warm home, movement and careful use of heat sources help most.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/multiple-sclerosis-cold-weatherhttps://www.heatjac.com/knowledge/multiple-sclerosis-cold-weatherTue, 29 Sep 2026 05:00:00 GMTCold weather can make some MS symptoms temporarily worse, most often muscle stiffness, spasms, fatigue and walking. Cold sensitivity is less common than heat sensitivity in MS, and the change usually fades once you warm up again. The practical goal is to stay steadily warm with layers and a warm home, while protecting skin that may not feel heat properly.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/feeling-cold-on-glp1-medicationshttps://www.heatjac.com/knowledge/feeling-cold-on-glp1-medicationsTue, 29 Sep 2026 04:59:00 GMTOzempic, Wegovy, Mounjaro and Zepbound do not list feeling cold or chills as a side effect in their US prescribing information, yet many people say they feel colder while taking them. Eating less and losing body fat are the most plausible reasons, since both are linked to lower heat production or less insulation. Persistent or extreme cold deserves a check with your clinician.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/cold-sensitivity-after-chemotherapyhttps://www.heatjac.com/knowledge/cold-sensitivity-after-chemotherapyTue, 29 Sep 2026 04:58:00 GMTOxaliplatin cold sensitivity usually starts within hours to 2 days after a dose and fades within 14 days, according to the FDA label, but it often returns with each dose and can last longer as cycles add up. Cold drinks, cold air and cold metal are the usual triggers. Room temperature drinks, gloves and a scarf help, and fever during chemotherapy needs an immediate call.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/prosthesis-cold-weather-tipshttps://www.heatjac.com/knowledge/prosthesis-cold-weather-tipsTue, 29 Sep 2026 04:57:00 GMTCold weather can make a residual limb painful, change how the socket fits as limb volume shifts, and trap sweat when you move from the cold into heated rooms. Keep the limb covered and dry, carry extra prosthetic socks, check your skin every morning and night, and keep batteries warm. Never put heat directly on skin with reduced sensation.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/staying-warm-in-a-wheelchairhttps://www.heatjac.com/knowledge/staying-warm-in-a-wheelchairTue, 29 Sep 2026 04:56:00 GMTTo stay warm in a wheelchair, wear loose layers of wool or synthetic fabric, add a hat, warm socks and lined waterproof boots, and cover your lap and legs with a wheelchair poncho or zippered blanket. Use gloves that still grip the push rims. Charge power chairs every night, and keep heat sources off skin you cannot feel well.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/spinal-cord-injury-temperature-regulationhttps://www.heatjac.com/knowledge/spinal-cord-injury-temperature-regulationTue, 29 Sep 2026 04:55:00 GMTAfter a spinal cord injury, especially at or above T6, the brain loses much of its connection to the skin, blood vessels and sweat glands below the injury. Shivering and sweating work only above that level, so body temperature tends to drift with the room or the weather. This is called poikilothermia. Managing it means controlling the environment, dressing well and avoiding direct heat sources.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/health-and-disability-warmth-guidehttps://www.heatjac.com/knowledge/health-and-disability-warmth-guideTue, 29 Sep 2026 04:54:00 GMTMany health conditions and disabilities change how the body makes heat, holds on to it or senses it. Nerve damage, poor circulation, numb skin, some medicines and moving less all play a part. The safest approach is similar across conditions: keep the home warm, hold in body heat with layers, keep direct heat off skin that cannot feel it, eat and drink regularly, and know the signs of hypothermia.Everyday Life and HealthHealth and Disabilityhttps://www.heatjac.com/knowledge/gifts-for-nurses-cold-shiftshttps://www.heatjac.com/knowledge/gifts-for-nurses-cold-shiftsMon, 28 Sep 2026 20:20:00 GMTThe best warm gifts for nurses split into two groups: items they can actually wear at work within their facility's attire policy, such as a low-lint base layer, warm socks in approved colors or a thin core layer under scrubs, and items for off shift, such as a warm commute layer or bedding for daytime sleep. Avoid bulky, hard-to-launder or battery-powered items unless their unit allows them.HealthcareBuyer's Guidehttps://www.heatjac.com/knowledge/firefighter-winter-operationshttps://www.heatjac.com/knowledge/firefighter-winter-operationsMon, 28 Sep 2026 14:54:00 GMTWinter fires combine two opposite threats. Interior work soaks crews in sweat inside heavy turnout gear, then exterior work, water spray and wind chill them fast. Safe cold weather operations rely on early crew rotation, a heated and sheltered rehab area with dry layers and warm fluids, medical monitoring as NFPA 1584 describes, and constant attention to ice underfoot.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/gifts-for-older-parent-warmthhttps://www.heatjac.com/knowledge/gifts-for-older-parent-warmthFri, 25 Sep 2026 19:55:00 GMTThe best warm gifts for an elderly parent are easy to put on, safe to use alone and suited to where they spend the day: soft layers with simple fastenings, a lap throw, warm socks and closed-back slippers with grippy soles, and bedding for cool nights. Anything that heats should have automatic shut-off and simple controls, and should never sit on skin they cannot feel well.Everyday Life and HealthBuyer's Guidehttps://www.heatjac.com/knowledge/stay-warm-winter-commutehttps://www.heatjac.com/knowledge/stay-warm-winter-commuteFri, 25 Sep 2026 17:26:00 GMTTo stay warm on a winter commute without overheating, dress in thin removable layers instead of one heavy coat, choose outer layers with full zippers you can open, and cover your head, hands and neck for the cold stretches. Vent or remove a layer before you start to sweat, especially on crowded trains, because damp clothing chills you once you step back outside.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/pharmaceutical-cold-chain-workhttps://www.heatjac.com/knowledge/pharmaceutical-cold-chain-workFri, 25 Sep 2026 15:12:00 GMTWorking in pharmaceutical cold storage means two different kinds of cold. Refrigerated rooms at 2 to 8°C bring long, moderate exposure that calls for insulated layers and warm-up breaks. Ultra-cold freezers, dry ice and liquid nitrogen bring brief but extreme contact hazards, plus gas buildup, that call for cryogenic gloves, face protection, ventilation and training.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/stay-warm-dog-walks-short-tripshttps://www.heatjac.com/knowledge/stay-warm-dog-walks-short-tripsFri, 25 Sep 2026 12:25:00 GMTTo stay warm on a dog walk or quick chore, dress as if you will be out longer than planned: a warm core layer, a windproof shell, a hat, gloves and a face covering. Wear boots with real traction for ice. Keep a grab-and-go kit by the door, and treat snow shoveling as hard exercise, not a small errand.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/gifts-for-raynaudshttps://www.heatjac.com/knowledge/gifts-for-raynaudsThu, 24 Sep 2026 20:11:00 GMTGood gifts for someone with Raynaud's help them stay warm through ordinary moments: a core layer or wrap, mittens with liners, thermal socks, insulated mugs, gloves for the freezer and warm bedtime layers. Raynaud's groups advise keeping the whole body warm, not just the fingers, so layers for the torso and neck are often as welcome as anything for the hands.Everyday Life and HealthBuyer's Guidehttps://www.heatjac.com/knowledge/stay-warm-outdoor-sporting-eventshttps://www.heatjac.com/knowledge/stay-warm-outdoor-sporting-eventsThu, 24 Sep 2026 17:41:00 GMTTo stay warm at a football game, sit on an insulated seat pad so cold bleachers cannot pull heat from your body, then wear loose layers under a windproof shell. Cover your feet, hands and head and keep them dry, bring warmers if the venue allows them, drink warm non-alcoholic fluids and take short warm-up walks. The same plan works for any outdoor sporting event.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/feeling-cold-or-hot-during-pregnancyhttps://www.heatjac.com/knowledge/feeling-cold-or-hot-during-pregnancyThu, 24 Sep 2026 14:36:00 GMTMany people feel warmer than usual during pregnancy because metabolism, blood volume and blood flow to the skin all rise. Feeling always cold during pregnancy is less typical and can be linked to anemia, an underactive thyroid, low blood pressure, poor sleep or inactivity. Gentle warming and cooling are fine, but avoid anything that raises core temperature, such as hot tubs and saunas.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/stay-warm-static-post-securityhttps://www.heatjac.com/knowledge/stay-warm-static-post-securityThu, 24 Sep 2026 12:40:00 GMTTo stay warm standing outside all day, insulate yourself from the ground first with insulated boots and a mat, then block the wind with shelter or a windproof layer. Wear adjustable layers that fit under your uniform and duty gear, add a heat source if your post allows it, take scheduled warm-up breaks, and eat and drink warm, non-alcoholic fluids through the shift.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/gifts-for-someone-always-coldhttps://www.heatjac.com/knowledge/gifts-for-someone-always-coldWed, 23 Sep 2026 19:38:00 GMTThe best gifts for someone who is always cold match where they feel it: a layer for the torso at home or the office, warm socks and slippers for cold floors, a mitten-and-liner setup for the commute, and safe bedtime warmth. Look for layers they will wear daily, simple controls and auto shut-off on anything that plugs in or heats up.Everyday Life and HealthBuyer's Guidehttps://www.heatjac.com/knowledge/cooling-under-ppe-and-body-armorhttps://www.heatjac.com/knowledge/cooling-under-ppe-and-body-armorWed, 23 Sep 2026 17:53:00 GMTBody armor, surgical gowns and protective suits trap heat because they block sweat evaporation and add weight. Cooling under them works best with phase-change, ice or liquid-cooled vests, which cool by conduction rather than evaporation. Studies show these vests improve comfort and cut heat storage, but packs can run out in under an hour under heavy gear, so planned swaps matter.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/sterile-processing-temperature-and-comforthttps://www.heatjac.com/knowledge/sterile-processing-temperature-and-comfortWed, 23 Sep 2026 15:20:00 GMTSterile processing departments set temperature by area. Under ASHRAE Standard 170 (2013 edition as amended by Addendum h), decontamination rooms are designed for 60°F to 73°F, clean workrooms for 68°F to 73°F with humidity at or below 60%, and sterile storage for a maximum of 75°F and 60% humidity. Decontamination runs cool largely because technicians work in heavy, fluid-resistant PPE that traps body heat.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/modular-heating-and-cooling-garmentshttps://www.heatjac.com/knowledge/modular-heating-and-cooling-garmentsWed, 23 Sep 2026 12:09:00 GMTA modular heating and cooling garment is an insulated vest or harness with interior pockets that accept either warming inserts, such as air-activated warmers or battery heaters, or cooling inserts, such as ice or phase-change packs. Insulation slows heat flow in both directions, so the same shell can hold warmth in during winter and keep a cold pack's cooling directed at the body in summer.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/employer-thermal-gear-bulk-buying-guidehttps://www.heatjac.com/knowledge/employer-thermal-gear-bulk-buying-guideTue, 22 Sep 2026 20:27:00 GMTTo buy cold weather gear for employees in bulk, start with a needs assessment by job, not a single catalog order. Run a sizing session and a short wear trial, send suppliers a written spec sheet, then negotiate minimum order quantities, warranty, returns and replacement terms. Plan laundering and, for battery-heated items, a controlled charging area before the first box arrives.Work and DutyBuyer's Guidehttps://www.heatjac.com/knowledge/menopause-hot-flashes-coolinghttps://www.heatjac.com/knowledge/menopause-hot-flashes-coolingTue, 22 Sep 2026 17:47:00 GMTHot flashes happen when falling estrogen makes the brain's temperature control more sensitive, triggering sudden flushing and sweating. Fans, layers, a cool bedroom and wearable cooling can make episodes more comfortable. The evidence is clear on one point, though: The Menopause Society does not recommend cooling techniques as a treatment for hot flashes, and effective treatments exist, so bothersome symptoms deserve a clinician's input.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/cold-dental-operatoryhttps://www.heatjac.com/knowledge/cold-dental-operatoryTue, 22 Sep 2026 14:48:00 GMTDental offices often feel cold because the room is set for a team that is moving, standing under bright lights and wearing gowns, masks, gloves and eye protection, while the patient lies still in a reclined chair. Stillness and nervousness both cool the hands and feet. Patients can bring a layer or ask for a blanket; practices can offer blankets and set zones sensibly.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/cooling-vests-for-workershttps://www.heatjac.com/knowledge/cooling-vests-for-workersTue, 22 Sep 2026 12:07:00 GMTOn construction and industrial sites, the most practical cooling vests are phase-change or hybrid designs with swappable packs, because they work in humid heat and under protective gear. Evaporative vests suit dry climates and light tasks. Research on construction workers suggests cooling vests are most useful during rest breaks, helping crews unload heat before the next work bout, alongside water, shade and acclimatization.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/warming-garment-buying-checklisthttps://www.heatjac.com/knowledge/warming-garment-buying-checklistMon, 21 Sep 2026 19:49:00 GMTBefore buying any warming garment, check seven things: the use case, safety marks and recall history, fit over your real layers, the care label, the written warranty and return terms, whether your workplace or airline allows it, and the cost over a full season. The checklist works for heated, heat-reflective, insulated and warmer-pocket garments alike.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/workplace-heat-stress-preventionhttps://www.heatjac.com/knowledge/workplace-heat-stress-preventionMon, 21 Sep 2026 17:31:00 GMTEmployers prevent heat stress with a written plan built on water, rest, shade, gradual acclimatization, training and a ready emergency response, backed by engineering controls such as ventilation and shade. As of September 2026, OSHA's proposed federal heat rule is not final, but employers remain responsible for heat hazards under the General Duty Clause and a revised National Emphasis Program.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/keeping-dialysis-and-infusion-patients-warmhttps://www.heatjac.com/knowledge/keeping-dialysis-and-infusion-patients-warmMon, 21 Sep 2026 15:05:00 GMTFeeling cold during dialysis is common and usually has several overlapping causes: some of your blood is circulating outside your body, the dialysate may be set slightly cool to help keep blood pressure stable, anemia reduces heat production, your access arm stays uncovered, and you sit still for hours. Infusion patients face similar factors. Layers, blankets and a word with your care team usually help.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/heat-stress-vs-heat-strokehttps://www.heatjac.com/knowledge/heat-stress-vs-heat-strokeMon, 21 Sep 2026 12:36:00 GMTHeat stress is the total heat load from weather, work and clothing. Heat exhaustion is an illness it can cause, with heavy sweating, headache, nausea, dizziness and weakness. Heat stroke is a medical emergency: the body's temperature control fails, core temperature can exceed 106°F, and confusion, slurred speech, seizures or collapse follow. Suspected heat stroke means calling 911 and cooling the person immediately.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/warming-cost-per-shifthttps://www.heatjac.com/knowledge/warming-cost-per-shiftFri, 18 Sep 2026 20:02:00 GMTOver a season, disposable warmers cost little per shift but add up with every shift, while a battery-heated vest costs more up front and very little to run. Using listed prices and a 100-shift illustrative season, one pair of warmers a shift runs about $69 to $149 per worker, and a $180 heated vest pays back in about two to three seasons.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/cooling-vests-for-mshttps://www.heatjac.com/knowledge/cooling-vests-for-msFri, 18 Sep 2026 17:14:00 GMTMany people with multiple sclerosis find that heat temporarily worsens their symptoms, a response called Uhthoff's phenomenon. Cooling vests help keep body temperature down and support comfort in hot weather and during exercise. A 2023 review of 13 studies found cooling garments improved walking and mobility in people with MS. Cooling supports comfort; it is not a treatment for MS itself.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/can-you-catch-a-cold-from-being-coldhttps://www.heatjac.com/knowledge/can-you-catch-a-cold-from-being-coldFri, 18 Sep 2026 14:39:00 GMTYou cannot get a cold from being cold alone, because colds are caused by viruses, most often rhinoviruses. Being chilled may still matter. Research suggests that cooling the body or the inside of the nose can weaken local defenses, making it easier for a virus you have already picked up to take hold and cause symptoms.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/phase-change-cooling-vestshttps://www.heatjac.com/knowledge/phase-change-cooling-vestsFri, 18 Sep 2026 12:26:00 GMTA phase-change cooling vest holds packs of a material that absorbs heat as it melts, staying at a fixed temperature, often in the 20s Celsius, until it has fully liquefied. That gives steady, comfortable cooling instead of the harsh cold of ice. Runtime depends on pack mass and heat load: in one study under a heavy protective suit at 40°C, packs lasted about 50 minutes.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/how-many-hours-of-warmth-do-you-needhttps://www.heatjac.com/knowledge/how-many-hours-of-warmth-do-you-needThu, 17 Sep 2026 19:33:00 GMTPlan warmth for the hours you are actually cold, not the length of the shift. As labeled by their makers, air-activated hand warmers run up to about 10 hours and body warmers up to 18, while one 35 Wh heated vest pack is rated at about 3 hours on high and 10 on low. Cold, heat setting and a passive base layer change those numbers.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/how-cooling-vests-workhttps://www.heatjac.com/knowledge/how-cooling-vests-workThu, 17 Sep 2026 17:15:00 GMTCooling vests move heat out of the torso in one of four ways. Evaporative vests cool as soaked fabric dries. Ice and gel vests pull heat into frozen packs. Phase-change vests use packs that absorb heat while melting at a set temperature. Active vests pump chilled liquid or air through the garment. Each type trades cooling power against runtime, weight and humidity tolerance.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/do-hot-drinks-warm-youhttps://www.heatjac.com/knowledge/do-hot-drinks-warm-youThu, 17 Sep 2026 15:14:00 GMTPartly true. A hot drink makes you feel warmer and adds a small amount of heat, but not enough to meaningfully raise core temperature on its own. In the cold, its comfort and, if sweetened, its calories help more than its heat. In hot, dry conditions, research suggests a hot drink can even reduce stored body heat by triggering extra sweating.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/winter-camping-sleep-warmhttps://www.heatjac.com/knowledge/winter-camping-sleep-warmThu, 17 Sep 2026 12:31:00 GMTTo stay warm winter camping, hike in light wicking layers so you do not sweat, then add insulation as soon as you stop. At night, insulate from the ground with sleeping pads totaling an R-value of about 5.5 or more for very cold conditions, choose a bag rated below the expected low, change into dry clothes, eat, and warm up before getting in.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/thermal-vest-sizing-under-uniformshttps://www.heatjac.com/knowledge/thermal-vest-sizing-under-uniformsWed, 16 Sep 2026 20:18:00 GMTTo size a thermal vest for wear under scrubs, a uniform or body armor, measure your chest at its fullest point over the base layer you will actually wear, then compare it with the maker's chart. Aim for close contact without compression, a length that stays tucked under the outer layer, and no added bulk that changes how scrubs or armor fit.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/keeping-elderly-warmhttps://www.heatjac.com/knowledge/keeping-elderly-warmWed, 16 Sep 2026 17:37:00 GMTTo keep an elderly person warm safely, keep the home heated to at least 68 to 70°F, dress them in loose layers with socks, slippers and a hat, and offer warm meals and drinks. Check on them often, because older adults can develop hypothermia indoors without noticing. Use heating pads, electric blankets and heaters cautiously, since reduced sensation and some medications raise the risk of burns.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/does-alcohol-warm-you-uphttps://www.heatjac.com/knowledge/does-alcohol-warm-you-upWed, 16 Sep 2026 14:57:00 GMTNo. Alcohol makes you feel warmer, but it does not warm you up. It widens blood vessels in the skin, which brings warm blood to the surface and creates a flush of warmth while your core loses heat faster. It also dulls the brain's temperature control and can weaken shivering, which raises the risk of hypothermia in the cold.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/stay-warm-at-the-officehttps://www.heatjac.com/knowledge/stay-warm-at-the-officeWed, 16 Sep 2026 12:12:00 GMTTo stay warm in a cold office, add a thin base layer under your work clothes, keep a vest or cardigan at your desk, and wear warm socks and closed shoes. Warm your hands with a hot drink, take short walking breaks, and move away from vents. If you want a space heater, check your workplace rules first, and raise persistent cold with facilities.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/thermal-vest-infection-control-approvalhttps://www.heatjac.com/knowledge/thermal-vest-infection-control-approvalTue, 15 Sep 2026 19:41:00 GMTTo get a thermal vest approved for the OR or other clinical areas, start with your facility's written attire policy. Then take a short, documented request to the people who own each question: infection prevention for fabric and laundering, perioperative leadership for where it may be worn, value analysis for unit purchases, and biomedical or safety staff for anything with a battery.HealthcareBuyer's Guidehttps://www.heatjac.com/knowledge/motorcycle-riding-in-coldhttps://www.heatjac.com/knowledge/motorcycle-riding-in-coldTue, 15 Sep 2026 17:09:00 GMTRiding in the cold is harder than it feels at a standstill because speed creates its own wind chill. Stay warm by blocking wind completely with a windproof outer layer, layering insulation underneath, sealing gaps at the neck and wrists, and adding heated gear for long rides. Cold slows reaction time, so if you start shivering or feel clumsy, get off the road and warm up.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/do-you-lose-heat-through-your-headhttps://www.heatjac.com/knowledge/do-you-lose-heat-through-your-headTue, 15 Sep 2026 15:24:00 GMTNo. You do not lose most of your body heat through your head. An uncovered head loses heat at roughly the same rate as any other patch of exposed skin, so its share is close to its share of your surface area, often cited as about 7 to 10 percent. A hat still matters when the head is the main part left bare.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/skiing-snowboarding-warmthhttps://www.heatjac.com/knowledge/skiing-snowboarding-warmthTue, 15 Sep 2026 12:43:00 GMTTo stay warm skiing without overheating, wear a wicking merino or synthetic base layer, a light insulating mid layer, and a waterproof shell with vents, then adjust with zippers rather than extra bulk. Open vents on hard runs and close everything plus a neck gaiter for the lift. Wear one pair of thin ski socks, mittens on cold days, and never cotton.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/reflective-linings-comparedhttps://www.heatjac.com/knowledge/reflective-linings-comparedMon, 14 Sep 2026 20:26:00 GMTHeat-reflective linings differ mainly in how much of the surface is metal. Dot patterns trade some reflection for breathability, continuous metallized layers reflect more but can trap sweat unless perforated or breathable, and laminated films sit between the two depending on construction. Judge any lining by its metal coverage, a stated emittance measured to a named test method, and how it handles moisture.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/ice-fishing-stay-warmhttps://www.heatjac.com/knowledge/ice-fishing-stay-warmMon, 14 Sep 2026 17:23:00 GMTTo stay warm ice fishing, dress in wicking, insulating and windproof layers, wear insulated rubber-soled boots with wool socks, and get off the ice surface by standing or sitting on insulation. Block the wind with a shelter, keep your hands dry, and eat and drink regularly. If you use a heater, choose one rated for indoor use, ventilate, and run a carbon monoxide detector.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/extreme-cold-warnings-explainedhttps://www.heatjac.com/knowledge/extreme-cold-warnings-explainedMon, 14 Sep 2026 14:42:00 GMTAn Extreme Cold Warning is the National Weather Service's most serious cold alert. It means dangerously cold air temperatures or wind chills are expected or already happening. Avoid going outside; if you must, dress in layers, cover all exposed skin and tell someone where you are. A watch means the danger is possible, and an advisory means hazardous cold below warning level.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/stay-warm-huntinghttps://www.heatjac.com/knowledge/stay-warm-huntingMon, 14 Sep 2026 12:33:00 GMTTo stay warm while hunting, walk in cool and carry your insulation, because sweat soaked into clothing on the approach is what chills you later on stand. Once you sit, add a windproof insulated layer, a hat, and warm boots, and use hand and toe warmers before your extremities get cold. Eat, drink, and get up and move if you start shivering hard.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/7v-vs-12v-heated-gearhttps://www.heatjac.com/knowledge/7v-vs-12v-heated-gearFri, 11 Sep 2026 19:57:00 GMTNot by itself. Heat output depends on watts, which designers can reach at 7.4V or 12V. A 12V system often supports more heating zones or higher peak output, and tool-battery gear lets you share packs, but runtime depends on watt-hours divided by watts, not voltage. Choose on rated watts, pack watt-hours, weight, and the battery ecosystem you already own.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/best-base-layer-materialshttps://www.heatjac.com/knowledge/best-base-layer-materialsFri, 11 Sep 2026 17:51:00 GMTThe best base layer for cold weather is merino wool or a synthetic such as polyester, chosen by activity. Synthetics wick sweat fastest and dry quickest, so they suit hard exertion. Merino feels warm when slightly damp and resists odor over several days of wear. Silk is light and soft for low-exertion use. Cotton holds moisture and dries slowly, so avoid it in the cold.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/winter-running-walking-layershttps://www.heatjac.com/knowledge/winter-running-walking-layersFri, 11 Sep 2026 15:09:00 GMTFor cold-weather running, dress as if it is about 20 degrees warmer than the actual temperature, so you feel slightly chilly at the start. Wear a wicking base layer, an insulating layer as it gets colder, and a wind-resistant shell, plus gloves and a hat below about 40°F. Walkers make less heat, so they need warmer layers than runners.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/how-to-layer-for-cold-weatherhttps://www.heatjac.com/knowledge/how-to-layer-for-cold-weatherFri, 11 Sep 2026 12:26:00 GMTLayering for cold weather means wearing three kinds of clothing that each do one job. A snug base layer moves sweat off your skin, an insulating mid layer such as fleece, down or synthetic fill holds warm air, and an outer shell blocks wind and precipitation. Because each layer comes off or goes on independently, you can stay warm without getting soaked in sweat.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/heated-gloves-vs-liners-vs-mittenshttps://www.heatjac.com/knowledge/heated-gloves-vs-liners-vs-mittensThu, 10 Sep 2026 20:09:00 GMTChoose on how much finger work you do. Heated gloves give adjustable heat with moderate dexterity but add battery weight and cost. Glove liners keep fingers covered for fine tasks but add little warmth alone. Mittens with a warmer pocket are the warmest simple option for waiting and walking, with the least dexterity. Many people use a liner under a mitten and add heat when needed.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/how-clothing-warmth-is-testedhttps://www.heatjac.com/knowledge/how-clothing-warmth-is-testedThu, 10 Sep 2026 17:36:00 GMTClothing warmth is tested at three levels. Fabrics are measured on sweating guarded hotplates (ISO 11092) for thermal and vapor resistance. Complete outfits are measured on heated thermal manikins (ASTM F1291, ISO 15831), with results in clo. Heat-reflective surfaces are rated for emittance with instruments such as portable emissometers (ASTM C1371). Each test answers a different question.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/winter-car-emergency-kithttps://www.heatjac.com/knowledge/winter-car-emergency-kitThu, 10 Sep 2026 14:51:00 GMTA winter car emergency kit should keep you warm, visible and able to get moving: blankets or a sleeping bag, extra hats, mittens and boots, water and snacks, a flashlight, a phone charger, a first aid kit, a shovel, an ice scraper, sand or kitty litter, jumper cables and flares or reflective triangles. If stranded, stay with the car and keep the tailpipe clear.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/clothing-microclimatehttps://www.heatjac.com/knowledge/clothing-microclimateThu, 10 Sep 2026 12:38:00 GMTThe clothing microclimate is the thin layer of air trapped between your skin and your clothing. Its temperature, humidity and thickness largely decide how warm and dry you feel. Comfortable conditions are often described as about 32°C and 50% relative humidity. Still air in gaps of up to about a centimeter insulates well; wind, movement and moisture disrupt it.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/battery-heat-vs-hand-warmers-cost-runtimehttps://www.heatjac.com/knowledge/battery-heat-vs-hand-warmers-cost-runtimeWed, 09 Sep 2026 19:44:00 GMTIf you use warmers only a few days a year, air-activated packs cost less and need no charging. If you use them most days of the season, rechargeable battery warmers usually pay for themselves within about 50 to 100 days of use, because a charge costs under a cent. The trade-offs are shorter runtime per charge, cold-weather battery loss and battery disposal.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/military-cold-weather-layeringhttps://www.heatjac.com/knowledge/military-cold-weather-layeringWed, 09 Sep 2026 17:24:00 GMTMilitary cold-weather layering rests on one idea: stay warm without getting wet. The Army's COLD rule says keep clothing clean, avoid overheating, wear it loose and in layers, and keep it dry. In practice that means a wicking base, removable insulation, a wind or waterproof shell, and a heavy insulated layer added only when you stop moving.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/how-to-dress-a-baby-for-cold-weatherhttps://www.heatjac.com/knowledge/how-to-dress-a-baby-for-cold-weatherWed, 09 Sep 2026 15:18:00 GMTThe American Academy of Pediatrics (AAP) says a baby only needs one more layer than you would wear in the same environment. Outdoors, add a hat, mittens and booties. For sleep, use layers or a wearable blanket instead of loose blankets, and do not put a hat on your baby indoors. Watch for sweating, a hot chest or flushed skin, which signal overheating.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/batteries-in-extreme-coldhttps://www.heatjac.com/knowledge/batteries-in-extreme-coldWed, 09 Sep 2026 12:41:00 GMTCold slows the chemistry inside a battery, so it delivers less capacity and power until it warms up. Battery University reports that a battery giving full capacity at 27 °C typically gives about half at minus 18 °C. The loss is mostly temporary, but charging lithium-ion cells below freezing can cause permanent damage through lithium plating.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/heated-vest-vs-reflective-vesthttps://www.heatjac.com/knowledge/heated-vest-vs-reflective-vestTue, 08 Sep 2026 20:31:00 GMTBuy a heated vest when you stand or sit still in real cold for hours and can charge every day. Buy a heat-reflective vest when you move a lot, work where batteries need approval, get wet, or want a layer that never runs down. Many buyers end up with a heat-reflective or insulated vest plus pockets for added heat on the coldest days.Technology and GearBuyer's Guidehttps://www.heatjac.com/knowledge/heated-gear-under-body-armorhttps://www.heatjac.com/knowledge/heated-gear-under-body-armorTue, 08 Sep 2026 17:10:00 GMTStaying warm under body armor is mostly about managing sweat. A carrier blocks ventilation and presses on anything worn beneath it, so the usual approach is a thin, moisture-managing base layer under the armor, insulation added over the kit when you stop moving, and, where policy allows, low-profile heat sources placed so nothing hot is pressed against bare skin.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/winter-coats-and-car-seatshttps://www.heatjac.com/knowledge/winter-coats-and-car-seatsTue, 08 Sep 2026 14:33:00 GMTBulky winter coats and snowsuits should not be worn under a car seat harness. In a crash, the padding flattens instantly and leaves slack, so a child can slip through the straps. The AAP and NHTSA recommend thin layers under a snug harness, then a blanket or the coat worn backwards over the buckled straps.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/radiant-barrier-clothinghttps://www.heatjac.com/knowledge/radiant-barrier-clothingTue, 08 Sep 2026 12:20:00 GMTA radiant barrier in clothing is a thin, low-emissivity metallic layer that reflects infrared heat radiated by your body back toward you and radiates little heat outward itself. It works only when it faces an air space, and it addresses radiant heat loss, not conduction, wind or evaporation. It matters most in still, cold conditions and in low-bulk layers.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/motorcycle-warmth-buyers-guidehttps://www.heatjac.com/knowledge/motorcycle-warmth-buyers-guideMon, 07 Sep 2026 19:52:00 GMTMost riders should start with wind protection and good layers, then add heated gear. Bike-powered 12V gear gives the most heat for as long as you ride, but only if your charging system has spare watts and the harness is fused correctly. Battery-powered gear needs no wiring and works off the bike, with shorter runtime. A controller lets you match heat to speed and temperature.Everyday Life and HealthBuyer's Guidehttps://www.heatjac.com/knowledge/wind-chill-explainedhttps://www.heatjac.com/knowledge/wind-chill-explainedMon, 07 Sep 2026 17:49:00 GMTWind chill is the temperature it feels like on exposed skin when wind and cold combine. Wind strips away the thin layer of warm air around your skin, so skin cools faster than it would in still air. The U.S. National Weather Service index, in use since November 2001, models heat loss from a face at walking pace and estimates how quickly frostbite can occur.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/keeping-kids-warm-outdoorshttps://www.heatjac.com/knowledge/keeping-kids-warm-outdoorsMon, 07 Sep 2026 15:06:00 GMTTo dress kids for cold weather, the American Academy of Pediatrics (AAP) recommends several thin layers plus insulated boots, mittens or gloves, and a hat. Young children usually need one more layer than an adult in the same conditions. Change wet clothing right away, limit outdoor time with regular indoor breaks, and avoid outdoor play when temperatures or wind chills fall below -15°F.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/normal-body-temperature-thermoregulationhttps://www.heatjac.com/knowledge/normal-body-temperature-thermoregulationMon, 07 Sep 2026 12:16:00 GMTNormal adult body temperature is a range, roughly 97 to 99 °F (36.1 to 37.2 °C), not a single number. It is lowest in the early morning, around 4 AM, and highest in the late afternoon. Rectal readings run a little higher than oral ones, and armpit readings lower. Below 95 °F (35 °C) is hypothermia; above 100.4 °F (38 °C) generally means fever.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/ice-fishing-warmth-buyers-guidehttps://www.heatjac.com/knowledge/ice-fishing-warmth-buyers-guideFri, 04 Sep 2026 20:14:00 GMTFor ice fishing, buy safety and warmth together: a flotation-assist jacket and bib suit or a foam life jacket, ice picks, cleats and a way to check thickness, then insulated waterproof boots, a two-glove system, and layers underneath. If you heat a shelter, choose a heater rated for indoor use, keep vents open, and run a carbon monoxide detector.Everyday Life and HealthBuyer's Guidehttps://www.heatjac.com/knowledge/why-hands-get-cold-firsthttps://www.heatjac.com/knowledge/why-hands-get-cold-firstFri, 04 Sep 2026 17:55:00 GMTHands and feet get cold first because, when the body senses cold, it narrows blood vessels in the skin of the extremities to keep warm blood near the vital organs. Fingers and toes also have a large surface area for their small volume and sit far from the core, so they lose heat quickly once warm blood flow drops.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/best-bedroom-temperature-for-sleephttps://www.heatjac.com/knowledge/best-bedroom-temperature-for-sleepFri, 04 Sep 2026 14:44:00 GMTFor most healthy adults, the best temperature for sleep is a cool room of about 60 to 68 degrees Fahrenheit (15 to 20 degrees Celsius), with 65 degrees a common starting point. A cool room supports the natural drop in core temperature that comes with sleep. Older adults often sleep better warmer, and babies have their own safe range.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/conductive-heat-losshttps://www.heatjac.com/knowledge/conductive-heat-lossFri, 04 Sep 2026 12:20:00 GMTConductive heat loss is the transfer of body heat directly into a colder object you touch, such as a metal tool, cold ground, a wet shirt or water. Its rate depends on the temperature difference, contact area and the material's thermal conductivity. Water conducts heat roughly 25 times better than air, and metals conduct far more, which is why they drain warmth so quickly.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/hunting-warmth-buyers-guidehttps://www.heatjac.com/knowledge/hunting-warmth-buyers-guideThu, 03 Sep 2026 19:36:00 GMTFor cold hunts, spend first on warm, dry feet and a packable insulating layer you put on at the stand, then on a merino or synthetic base layer, a quiet windproof outer layer, and a hand muff. Heated or warmer-pocket vests are the next upgrade for long sits. Check your state's blaze orange rules before choosing outer layers.Everyday Life and HealthBuyer's Guidehttps://www.heatjac.com/knowledge/clo-value-explainedhttps://www.heatjac.com/knowledge/clo-value-explainedThu, 03 Sep 2026 17:24:00 GMTA clo is the standard unit of clothing insulation. One clo equals a thermal resistance of 0.155 square meter kelvin per watt, roughly the insulation of a typical business suit, and a nude body is 0 clo. Higher clo means more resistance to dry heat loss. Values are measured on heated manikins and are used in comfort standards such as ASHRAE 55.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/ems-cold-weather-gear-guidehttps://www.heatjac.com/knowledge/ems-cold-weather-gear-guideThu, 03 Sep 2026 14:41:00 GMTEMS crews stay warmest with a system built for constant transitions: a wicking base layer, a light insulating mid layer that comes off easily in the heated rig, a fluid-resistant outer shell that can be cleaned or laundered after contamination, sturdy insulated boots, and a glove system that separates exam gloves for patient care from insulated gloves for scene work.Work and DutyBuyer's Guidehttps://www.heatjac.com/knowledge/what-is-emissivityhttps://www.heatjac.com/knowledge/what-is-emissivityThu, 03 Sep 2026 12:28:00 GMTEmissivity is a number from 0 to 1 that describes how efficiently a surface gives off thermal (infrared) radiation compared with a perfect emitter at the same temperature. For opaque materials, emissivity and reflectance add up to 1, so a surface with low emissivity reflects most incoming infrared. Human skin sits near 0.98, while bright aluminum can be as low as 0.02 to 0.03.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/police-security-cold-weather-gearhttps://www.heatjac.com/knowledge/police-security-cold-weather-gearWed, 02 Sep 2026 20:22:00 GMTFor winter duty, buy in this order: a thin wicking base layer that fits under armor, a low-bulk insulated vest or fleece that fits under the duty jacket, insulated waterproof boots with wool socks, and two weights of gloves you have trained in. Add heated or warmer-pocket gear for long static posts, and confirm everything with your department's uniform policy.Work and DutyBuyer's Guidehttps://www.heatjac.com/knowledge/berry-amendment-textileshttps://www.heatjac.com/knowledge/berry-amendment-textilesWed, 02 Sep 2026 17:34:00 GMTThe Berry Amendment is a US law that bars the Department of Defense from spending its funds on clothing, textiles, food and certain other items unless they are grown, reprocessed, reused or produced in the United States. For textiles, the requirement reaches back through fabric to fibers and yarns. It is codified at 10 U.S.C. 4862 (formerly 2533a) and implemented through DFARS 252.225-7012.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/construction-utility-winter-gear-guidehttps://www.heatjac.com/knowledge/construction-utility-winter-gear-guideWed, 02 Sep 2026 15:17:00 GMTBuy winter work gear around the rules your outer layer must meet. Hi-vis stays outermost wherever traffic or equipment is present. Where arc flash is a hazard, every layer must be non-melting and the outer layer arc-rated. Within those limits, choose thin core warmth that fits under a harness, gloves matched to each task, and batteries you can charge somewhere warm.Work and DutyBuyer's Guidehttps://www.heatjac.com/knowledge/non-freezing-cold-injuryhttps://www.heatjac.com/knowledge/non-freezing-cold-injuryWed, 02 Sep 2026 12:42:00 GMTNon-freezing cold injury (NFCI) is damage to nerves, blood vessels and tissue, usually in the feet, caused by hours of cold, wet exposure above freezing. Trench foot and immersion foot are the classic forms. The Army describes risk at air temperatures of 32 to 55 °F, and the CDC notes trench foot can occur up to 60 °F if feet stay wet.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/cold-storage-worker-gear-guidehttps://www.heatjac.com/knowledge/cold-storage-worker-gear-guideTue, 01 Sep 2026 19:48:00 GMTCold storage PPE depends on the zone and the time spent inside. Coolers near 32 °F (0 °C) usually need warm layers, dexterity gloves and insulated footwear. Freezers need an insulated suit or jacket and bib, liner plus insulated gloves or mittens, insulated boots and a head cover. Blast freezers, down to about -22 °F (-30 °C), also need strict warm-up breaks.Work and DutyBuyer's Guidehttps://www.heatjac.com/knowledge/prehospital-hypothermia-preventionhttps://www.heatjac.com/knowledge/prehospital-hypothermia-preventionTue, 01 Sep 2026 17:34:00 GMTPrehospital hypothermia prevention works in layers: get the patient off cold ground, remove wet clothing, block wind and moisture, add insulation, then add external heat to the torso without direct skin contact. Heat-reflective wraps and vapor barriers limit loss; insulated wraps trap still air; chemical and battery warmers add heat. Military guidance rates simple space blankets as the least effective option on their own.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/thermal-gear-for-dental-teamshttps://www.heatjac.com/knowledge/thermal-gear-for-dental-teamsTue, 01 Sep 2026 14:52:00 GMTDental team members should buy warmth that lives under the protective gown or lab coat: a thin base layer or close-fitting vest, with sleeves that stay clear of glove cuffs. Warm hands between patients, then perform hand hygiene before gloving. Choose layers the practice can launder under its policy, and for a team, approve a short list of options rather than one item for everyone.HealthcareBuyer's Guidehttps://www.heatjac.com/knowledge/trauma-hypothermia-lethal-triadhttps://www.heatjac.com/knowledge/trauma-hypothermia-lethal-triadTue, 01 Sep 2026 12:25:00 GMTThe lethal triad is the combination of hypothermia, acidosis and coagulopathy in severely injured patients. Each worsens the others: cold slows clotting enzymes, poor perfusion causes acidosis, and uncontrolled bleeding deepens both. Military trauma guidance reports that hypothermic trauma patients die at about twice the rate of similarly injured patients with normal temperature, so heat loss is treated as a threat from the point of injury.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/thermal-gear-for-anesthesia-providershttps://www.heatjac.com/knowledge/thermal-gear-for-anesthesia-providersMon, 31 Aug 2026 20:05:00 GMTAnesthesia providers are often the coldest people in the operating room: seated, in scrubs alone, near the supply airflow, for hours. Buy for that position. Prioritize core warmth, sleeves that stay clear of lines and monitors, low bulk at the chest and shoulders, quiet fabrics and closures, and heat you can adjust without leaving the patient. Passive layers avoid most battery policy questions.HealthcareBuyer's Guidehttps://www.heatjac.com/knowledge/hypothermia-prevention-management-kithttps://www.heatjac.com/knowledge/hypothermia-prevention-management-kitMon, 31 Aug 2026 17:32:00 GMTThe Hypothermia Prevention and Management Kit (HPMK) is a compact casualty-warming kit used in military and tactical medicine. It pairs a chemical, air-activated heating liner with a hooded, heat-reflective vapor-barrier shell. Medics use it to limit heat loss in trauma casualties during care and evacuation. It is not insulated, so guidelines treat it as a short-term tool.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/thermal-gear-for-nurses-and-or-staffhttps://www.heatjac.com/knowledge/thermal-gear-for-nurses-and-or-staffMon, 31 Aug 2026 15:08:00 GMTTo stay warm under scrubs, buy for your unit's rules first and warmth second: a close-fitting, low-lint base layer, a thin core vest that sits fully under the scrub top, and a warm-up jacket where arms may be covered. Choose fabrics you can launder the way your facility requires. Passive layers suit most units; battery-heated gear fits where devices are clearly allowed.HealthcareBuyer's Guidehttps://www.heatjac.com/knowledge/ecwcs-levels-explainedhttps://www.heatjac.com/knowledge/ecwcs-levels-explainedMon, 31 Aug 2026 12:39:00 GMTThe Extended Cold Weather Clothing System (ECWCS) Generation III is the US Army's 12-piece, seven-level layering system. Levels 1 and 2 are base layers, Level 3 is fleece, Level 4 a wind jacket, Level 5 soft shell, Level 6 a waterproof shell and Level 7 an insulated parka and trousers. The Army rates the full system for about minus 40 to plus 60 °F.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/heated-ppe-program-for-employershttps://www.heatjac.com/knowledge/heated-ppe-program-for-employersFri, 28 Aug 2026 17:48:00 GMTA heated and thermal PPE program starts with a documented cold hazard assessment, then specifies garments that pass seven checks: battery safety and charging, washing and care, sizing and fit, dexterity, compatibility with hi-vis and other PPE, a structured pilot with real crews, and a realistic cost per shift. Heated gear should supplement engineering controls, warm-up breaks and good layering, not replace them.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/space-heater-safetyhttps://www.heatjac.com/knowledge/space-heater-safetyFri, 28 Aug 2026 15:12:00 GMTSpace heater safety comes down to a few rules. Keep the heater at least 3 feet from anything that can burn, plug it directly into a wall outlet, and choose a model with a safety certification mark and automatic shut-off. Turn it off when you leave the room or go to sleep. Fuel-burning heaters also need proper venting and a working carbon monoxide alarm.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/winter-work-utilities-constructionhttps://www.heatjac.com/knowledge/winter-work-utilities-constructionFri, 28 Aug 2026 12:36:00 GMTTo stay warm working outside in winter, dress in three adjustable layers that fit under your harness and hi-vis, keep hands, feet and head dry and covered, and plan around wind chill rather than air temperature. Take warm-up breaks in a heated space, pair up to watch for early cold stress signs, and treat ice, winter driving and downed lines as part of the same plan.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/cold-and-worker-productivityhttps://www.heatjac.com/knowledge/cold-and-worker-productivityThu, 27 Aug 2026 17:18:00 GMTCold slows work long before it causes injury. As hands cool, finger sensitivity, grip and fine motor control fall, and muscles and joints stiffen. A 2025 study found sharp drops in manual dexterity once finger skin cooled to about 23°C, and a nationwide Italian study linked cold days to roughly 6,000 extra occupational injuries a year. Keeping hands and core warm protects both safety and output.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/electric-blanket-heating-pad-safetyhttps://www.heatjac.com/knowledge/electric-blanket-heating-pad-safetyThu, 27 Aug 2026 14:56:00 GMTElectric blankets and heating pads are safe for most adults when the product is in good condition, used flat, and switched off or on a timer before sleep. The main risks are fire, mostly from blankets over ten years old, and burns from long contact with warm surfaces. People who cannot feel heat well, including many with diabetes or neuropathy, and infants should not use them.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/cold-work-warm-up-scheduleshttps://www.heatjac.com/knowledge/cold-work-warm-up-schedulesThu, 27 Aug 2026 12:44:00 GMTThe most widely used cold work and warm-up schedule comes from the ACGIH Threshold Limit Value for cold stress. For moderate to heavy work over a four-hour period, it shortens the maximum work period and adds 10-minute warm-up breaks as air temperature falls and wind rises, starting at about -26°C (-15°F) with a 16 km/h (10 mph) wind, and stops non-emergency work at about -43°C (-45°F).Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/frostbite-vs-frostnip-vs-chilblainshttps://www.heatjac.com/knowledge/frostbite-vs-frostnip-vs-chilblainsWed, 26 Aug 2026 17:08:00 GMTFrostnip and frostbite are freezing injuries: frostnip is the mild, temporary surface stage, while frostbite freezes skin and deeper tissue below 0°C (32°F) and can cause permanent damage. Chilblains are not freezing injuries; they are itchy, red or purple patches that appear hours after repeated exposure to cold, damp air above freezing, and usually clear in 2 to 3 weeks.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/cold-feet-at-nighthttps://www.heatjac.com/knowledge/cold-feet-at-nightWed, 26 Aug 2026 15:21:00 GMTCold feet at night usually mean the small blood vessels in your feet are still narrowed to hold heat in your core, just when your body wants to release heat through the feet to fall asleep. Loose bed socks, a pre-warmed bed, and a warm bath one to two hours before bed help most people. Numbness, pain or one colder foot deserve a clinician's attention.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/cold-stress-symptoms-first-aidhttps://www.heatjac.com/knowledge/cold-stress-symptoms-first-aidWed, 26 Aug 2026 12:41:00 GMTCold stress shows up as shivering, fatigue, clumsiness and confusion (hypothermia), numb, tingling, pale or waxy skin (frostbite), and red, swollen, numb feet after wet cold (trench foot). First aid starts the same way: get the person out of the cold, remove wet clothing, warm them gently and call for medical help. Never rub frostbitten skin or use direct high heat.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/what-to-wear-in-a-freezer-warehousehttps://www.heatjac.com/knowledge/what-to-wear-in-a-freezer-warehouseTue, 25 Aug 2026 17:09:00 GMTDress for a freezer warehouse in three layers: a moisture-wicking base of wool or synthetic fabric, an insulating middle layer or freezer suit, and a wind-resistant outer layer. Add insulated gloves with liners, an insulated hat or hood, and insulated boots with dry socks. Avoid cotton, open layers before you sweat, and change damp items at every break.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/stay-warm-at-home-without-heatinghttps://www.heatjac.com/knowledge/stay-warm-at-home-without-heatingTue, 25 Aug 2026 14:38:00 GMTTo stay warm at home without turning up the heat, warm your body first: wear loose layers, keep your core, head and feet covered, eat regular meals and get up to move every hour. Then keep heat in: block drafts, close curtains at night, open sunny ones by day and heat only the room you use. Keep that room warm enough for health, especially for older adults and babies.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/working-in-a-freezer-health-riskshttps://www.heatjac.com/knowledge/working-in-a-freezer-health-risksTue, 25 Aug 2026 12:50:00 GMTWorking in a freezer is manageable when exposure is controlled, but it carries real risks: cold, painful hands and lost dexterity, frostbite on exposed or damp skin, whole-body cooling toward hypothermia, and strain from repeated moves between cold and warm zones. Research on cold store workers links long, repeated exposure to symptoms, while limited, well-managed entries show fewer lasting effects.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/osha-cold-stress-guidancehttps://www.heatjac.com/knowledge/osha-cold-stress-guidanceMon, 24 Aug 2026 17:40:00 GMTOSHA has no specific standard for cold stress and sets no minimum working temperature. Employers are covered by the General Duty Clause, Section 5(a)(1) of the OSH Act, which requires a workplace free from recognized hazards likely to cause death or serious harm, including cold. The PPE standard's hazard assessment and training duties also apply, while ordinary winter clothing is excepted from employer payment.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/stay-warm-power-outagehttps://www.heatjac.com/knowledge/stay-warm-power-outageMon, 24 Aug 2026 15:03:00 GMTTo stay warm without power, move everyone into one small room, close it off, and dress in loose layers with hats, socks and blankets. Eat regular meals, sip warm nonalcoholic drinks and keep moving. Never heat your home with a gas oven, grill, camp stove or generator indoors, because they produce deadly carbon monoxide. If the house keeps getting colder, go to a warming center.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/far-infrared-clothing-evidencehttps://www.heatjac.com/knowledge/far-infrared-clothing-evidenceMon, 24 Aug 2026 12:11:00 GMTFar-infrared (FIR) clothing contains mineral particles that absorb body heat and re-emit part of it as infrared energy. Physics allows a small effect on how heat moves, but a passive fabric cannot create energy. Controlled studies are few, small and mixed: some report modest changes in recovery or fatigue measures, and none show large warmth or health benefits. Read bold claims with caution.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/phase-change-material-clothinghttps://www.heatjac.com/knowledge/phase-change-material-clothingFri, 21 Aug 2026 17:28:00 GMTPhase-change materials (PCMs) are substances, often waxes, that melt and solidify near skin temperature. In clothing they are sealed in microcapsules or fibers. When you warm up, they absorb heat as they melt; when you cool down, they release it as they solidify. The effect is real but small and temporary, smoothing temperature swings rather than supplying lasting warmth.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/home-and-family-warmth-guidehttps://www.heatjac.com/knowledge/home-and-family-warmth-guideFri, 21 Aug 2026 14:47:00 GMTTo stay warm in winter at home, keep living spaces heated to a safe level, dress everyone in layers, and use every heat source carefully. Keep space heaters away from anything that can burn, never run generators or grills indoors, and install carbon monoxide alarms. Give babies one more layer than adults, keep bulky coats out of car seats, and plan ahead for outages and travel.Everyday Life and HealthHome and Familyhttps://www.heatjac.com/knowledge/aerogel-clothing-insulationhttps://www.heatjac.com/knowledge/aerogel-clothing-insulationFri, 21 Aug 2026 12:17:00 GMTAerogel is a solid made mostly of air, about 99.8% by volume, locked inside a nanoscale silica network. The tiny pores stop air from moving and carrying heat, so aerogel insulates well in very thin layers. In clothing it is usually bonded into flexible blankets or composites, which suits gloves, boots and slim jackets, though breathability, durability and cost remain trade-offs.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/how-space-blankets-workhttps://www.heatjac.com/knowledge/how-space-blankets-workThu, 20 Aug 2026 17:45:00 GMTA space blanket is a thin plastic film coated with vaporized aluminum. It works mainly by reflecting the infrared heat your body radiates back toward you, and secondarily by blocking wind and trapping moist air, which cuts convective and evaporative loss. It adds almost no insulation, so it cannot stop heat draining into cold ground and works best combined with a pad and insulating layers.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/do-reflective-linings-workhttps://www.heatjac.com/knowledge/do-reflective-linings-workThu, 20 Aug 2026 12:41:00 GMTYes, but modestly and conditionally. A heat-reflective lining such as Omni-Heat reduces the infrared heat your body radiates outward, so less warmth escapes through the jacket. The benefit is real, typically a percentage improvement rather than a dramatic one, and it is largest when radiant loss dominates, when the lining sits over good insulation with an air gap, and when paired with a heat source.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/how-to-choose-a-heated-vesthttps://www.heatjac.com/knowledge/how-to-choose-a-heated-vestWed, 19 Aug 2026 17:42:00 GMTThe best heated vest is the one that fits your use: snug enough for the panels to reach your body, heating zones where you feel cold, a battery with enough watt-hours for your day, and evidence of safety testing. Start by deciding whether you need added heat at all, then judge fit, zones, battery, safety and care, in that order.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/heated-socks-vs-heated-insoleshttps://www.heatjac.com/knowledge/heated-socks-vs-heated-insolesWed, 19 Aug 2026 12:11:00 GMTHeated socks usually warm the toes and top of the foot and work in almost any footwear, but they must be washed with care and carry the battery at the cuff. Heated insoles warm the sole from underneath, move easily between boots and hide the electronics, but take up room in the boot. Both carry burn and battery risks worth checking before you buy.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/battery-heated-vs-battery-free-warmthhttps://www.heatjac.com/knowledge/battery-heated-vs-battery-free-warmthTue, 18 Aug 2026 17:16:00 GMTBattery-heated clothing adds heat on demand and is best when you are still for long periods in real cold. Battery-free warmth, from insulation, heat-reflective linings and air-activated warmers, works by slowing heat loss or adding chemical heat, with no charging, less to fail and simpler travel. Many people get the best result by combining them: good layers first, added heat only where needed.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/are-hand-warmers-safehttps://www.heatjac.com/knowledge/are-hand-warmers-safeTue, 18 Aug 2026 12:48:00 GMTHand warmers are safe for most people when used as directed: inside a glove, pocket or over a layer of clothing, never directly on bare skin for long periods and never while asleep. They can reach temperatures well above the point where skin is injured, so children, older adults, people with diabetes or reduced sensation, and pregnant people need extra care.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/flying-with-heated-clothinghttps://www.heatjac.com/knowledge/flying-with-heated-clothingMon, 17 Aug 2026 17:40:00 GMTYou can fly with a heated vest or jacket, but the lithium-ion battery must travel in the cabin, never in checked baggage when it is a spare. Under FAA rules, packs up to 100 watt-hours need no airline approval, packs from 101 to 160 Wh need airline approval with a limit of two spares, and larger packs are forbidden.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/heated-vest-battery-guidehttps://www.heatjac.com/knowledge/heated-vest-battery-guideMon, 17 Aug 2026 12:24:00 GMTA heated vest battery's real capacity is its watt-hours (Wh), which you get by multiplying volts by amp-hours. Runtime is roughly that energy divided by how many watts the heating panels draw on a given setting. Milliamp-hours (mAh) alone can mislead, because packs run at different voltages, and cold weather temporarily cuts how much energy a lithium-ion pack can deliver.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/ptc-self-regulating-heatershttps://www.heatjac.com/knowledge/ptc-self-regulating-heatersFri, 14 Aug 2026 17:41:00 GMTA PTC (positive temperature coefficient) heater is an element whose electrical resistance rises sharply as it warms. As it heats, less current flows, so heat output drops on its own near a designed switching temperature. In wearables, PTC films and inks provide built-in temperature limiting without a separate sensor, but the set point is fixed at manufacture and does not replace good design.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/how-heated-vests-workhttps://www.heatjac.com/knowledge/how-heated-vests-workFri, 14 Aug 2026 12:12:00 GMTA heated vest works like a small, flexible electric blanket. A rechargeable battery pushes current through thin heating elements, usually carbon fiber or metal alloy wire, sewn into panels at the chest, back or collar. The elements resist the current and turn electrical energy into heat. A controller sets the heat level, and the vest's insulation holds that heat near your core.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/how-long-do-hand-warmers-lasthttps://www.heatjac.com/knowledge/how-long-do-hand-warmers-lastThu, 13 Aug 2026 17:39:00 GMTUnopened air-activated hand warmers keep for about 3 to 4 years, and the expiration date is printed on the outer wrapper: HotHands states a four-year shelf life and Ergodyne three years. Once opened, hand warmers are rated for about 7 to 12 hours of heat and body warmers up to 18 hours. Expired but sealed warmers often still work, though they may run shorter.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/how-hand-warmers-workhttps://www.heatjac.com/knowledge/how-hand-warmers-workThu, 13 Aug 2026 12:14:00 GMTDisposable hand warmers work by controlled rusting. When you open the wrapper, oxygen reaches a mix of iron powder, water, salt, activated carbon and an absorbent filler. The iron oxidizes to iron oxide and releases heat. Salt speeds the reaction, carbon spreads the heat, and the porous pouch limits airflow so warmth lasts for hours instead of minutes.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/can-you-wash-a-heated-vesthttps://www.heatjac.com/knowledge/can-you-wash-a-heated-vestWed, 12 Aug 2026 17:31:00 GMTMost heated vests can be washed, but only after the battery is removed and the connector is secured. Follow the care label first. When it allows machine washing, use a gentle cycle, cold water and mild detergent, then air dry completely before reconnecting power. Never tumble dry, iron, bleach or dry clean a garment with heating elements unless the label allows it.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/heated-vest-vs-heated-jackethttps://www.heatjac.com/knowledge/heated-vest-vs-heated-jacketWed, 12 Aug 2026 12:23:00 GMTA heated vest warms your torso, layers under almost anything and leaves arms free, which makes it the most versatile choice. A heated jacket adds sleeves and an outer shell, so it suits people who want one garment for wind and weather. A heated hoodie is a casual mid layer for mild cold, commuting and time around home.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/are-heated-vests-safehttps://www.heatjac.com/knowledge/are-heated-vests-safeTue, 11 Aug 2026 17:13:00 GMTFor most healthy adults, a well-made heated vest used as directed is a low-risk way to stay warm. The real hazards are skin burns from prolonged contact heat and fire from damaged or poorly made lithium batteries. People with reduced sensation, diabetes, implanted cardiac devices, pregnancy, young children and frail older adults need extra caution and a clinician's input.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/heated-clothing-diabetes-neuropathy-safetyhttps://www.heatjac.com/knowledge/heated-clothing-diabetes-neuropathy-safetyTue, 11 Aug 2026 12:40:00 GMTHeated clothing can be used by many people with diabetes, but neuropathy changes the risk. When nerves cannot sense heat properly, a heated panel, sock or hand warmer can burn skin without warning. Talk to your clinician first, avoid direct heat on numb areas, especially the feet, use the lowest effective setting, keep fabric between heat and skin, and check your skin every time.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/autoimmune-conditions-and-coldhttps://www.heatjac.com/knowledge/autoimmune-conditions-and-coldMon, 10 Aug 2026 17:07:00 GMTCold sensitivity is one of the most common experiences in scleroderma and lupus, mostly through secondary Raynaud's. Nearly 90% of people with scleroderma have Raynaud's symptoms, and it affects up to one-third of people with lupus. Living well in the cold means warming the whole body, protecting fragile skin, avoiding sudden temperature changes and reporting sores early to your care team.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/cold-intolerance-causeshttps://www.heatjac.com/knowledge/cold-intolerance-causesMon, 10 Aug 2026 12:19:00 GMTCold intolerance is an abnormal sensitivity to cold temperatures. MedlinePlus lists its main causes as anemia, hypothyroidism, blood vessel problems such as Raynaud's, anorexia nervosa, problems with the brain's temperature center and chronic severe illness. Some cancer drugs, notably oxaliplatin, also make people very sensitive to cold. A clinician can usually narrow the cause with an exam and blood tests.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/core-warmth-and-cold-handshttps://www.heatjac.com/knowledge/core-warmth-and-cold-handsFri, 07 Aug 2026 17:08:00 GMTYour body gives up hand warmth first when it senses cold. To protect core temperature, the hypothalamus narrows blood vessels in the skin, and fingers cool quickly. Keeping the torso warm reduces that signal, so the body has less reason to hold warm blood back from the hands. That is why Raynaud's organizations advise warming the whole body, especially the core, not only the fingers.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/best-gloves-for-raynauds-what-to-look-forhttps://www.heatjac.com/knowledge/best-gloves-for-raynauds-what-to-look-forFri, 07 Aug 2026 12:30:00 GMTThe best gloves for Raynaud's are usually not gloves at all but insulated, windproof mittens, because fingers share heat inside one space. Wear a thin liner glove underneath for tasks, and choose a long cuff and room for a hand warmer. Heated gloves suit some people on very cold days, but no glove works well if your core is cold.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/raynauds-vs-similar-conditionshttps://www.heatjac.com/knowledge/raynauds-vs-similar-conditionsThu, 06 Aug 2026 17:42:00 GMTRaynaud's causes short episodes in which fingers or toes turn white, then blue, then red. Chilblains are itchy red or purple patches that appear hours after cold. Acrocyanosis is persistent, usually painless blue discoloration. Erythromelalgia is red, burning skin triggered by warmth. Cold urticaria causes itchy welts within minutes. Buerger's disease is a tobacco-linked artery disease that can mimic Raynaud's.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/primary-vs-secondary-raynaudshttps://www.heatjac.com/knowledge/primary-vs-secondary-raynaudsThu, 06 Aug 2026 12:41:00 GMTPrimary Raynaud's happens on its own, usually starts in the teens or twenties, and is generally mild. Secondary Raynaud's is caused by another condition, medicine or exposure, often begins later in adulthood, and is more likely to cause finger sores. Clinicians tell them apart with a history, an exam, a look at the nailfold capillaries and blood tests such as ANA.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/cold-hands-and-feet-causeshttps://www.heatjac.com/knowledge/cold-hands-and-feet-causesWed, 05 Aug 2026 17:08:00 GMTCold hands and feet are usually the body's normal way of protecting core temperature by narrowing blood vessels in the skin. The pattern tells you more than the coldness itself: episodes of white or blue fingers suggest Raynaud's, one-sided coldness can point to blocked arteries, and numbness with cold feet may reflect nerve damage. Most people improve by warming the whole body.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/why-am-i-always-coldhttps://www.heatjac.com/knowledge/why-am-i-always-coldWed, 05 Aug 2026 12:42:00 GMTFeeling cold all the time is often a normal difference in how your body conserves heat, shaped by body size, activity and clothing. Persistent or worsening cold can also come from hypothyroidism, anemia, very low body weight, Raynaud's phenomenon or other blood vessel problems. If cold intolerance is long-term, extreme or comes with fatigue or other new symptoms, see a clinician.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/core-temperature-monitoring-methodshttps://www.heatjac.com/knowledge/core-temperature-monitoring-methodsTue, 04 Aug 2026 17:45:00 GMTCore temperature is best measured where blood from the body's core is sampled directly or closely: the pulmonary artery, distal esophagus, nasopharynx or tympanic membrane. Bladder, oral, axillary and zero-heat-flux forehead sensors are practical near-core options with known limits. Infrared temporal and ear scanners are not accurate enough to guide perioperative care, and NICE advises against indirect estimates.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/operating-room-temperature-humidity-standardshttps://www.heatjac.com/knowledge/operating-room-temperature-humidity-standardsTue, 04 Aug 2026 12:45:00 GMTIn the US, operating room design conditions come from ANSI/ASHRAE/ASHE Standard 170, which sets a temperature range of 68°F to 75°F (20°C to 24°C) and relative humidity of 20 to 60 percent. CMS lowered its minimum humidity from 35 to 20 percent in 2013. The UK's NICE guideline adds a patient-focused rule: at least 21°C (69.8°F) while the patient is exposed.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/passive-vs-active-warminghttps://www.heatjac.com/knowledge/passive-vs-active-warmingMon, 03 Aug 2026 17:19:00 GMTPassive warming reduces heat loss by insulating the patient with blankets, heat-reflective layers or clothing, but relies on the body's own heat. Active warming adds external heat through devices such as forced-air, resistive or circulating-water systems. In surgery, anesthesia blunts the body's heat production and defenses, so guidelines favor active warming for most anesthetized patients and use passive measures as support.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/forced-air-vs-conductive-warminghttps://www.heatjac.com/knowledge/forced-air-vs-conductive-warmingMon, 03 Aug 2026 12:12:00 GMTBoth forced-air and conductive warming reduce perioperative hypothermia, and neither eliminates it. Forced air has the larger evidence base and is NICE's default; some trials find it slightly more effective, while others find conductive warming equivalent or better, especially when combined with prewarming. Timing, coverage and consistent use often matter more than the choice of technology.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/conductive-patient-warming-explainedhttps://www.heatjac.com/knowledge/conductive-patient-warming-explainedFri, 31 Jul 2026 17:41:00 GMTConductive patient warming transfers heat through direct contact between a warm surface and the patient's skin. The two main forms are electric resistive systems, which pass a low-voltage current through a carbon or polymer fabric in blankets and mattresses, and circulating-water systems, which pump temperature-controlled water through pads or mattresses. NICE recommends considering resistive warming when forced air is unsuitable.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/forced-air-warming-explainedhttps://www.heatjac.com/knowledge/forced-air-warming-explainedFri, 31 Jul 2026 12:08:00 GMTForced-air warming blows heated, filtered air from a bedside unit through a hose into a disposable blanket or gown, which releases it through small perforations over the patient's skin. It warms by convection and also blocks radiant loss to the room. It is the most widely used active warming method in surgery and the default recommended by NICE for anesthesia longer than 30 minutes.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/prewarming-before-surgeryhttps://www.heatjac.com/knowledge/prewarming-before-surgeryThu, 30 Jul 2026 17:32:00 GMTPrewarming means actively warming a patient's skin, usually with a forced-air or conductive device, before anesthesia starts. It loads heat into the arms and legs so that less core heat is lost when anesthesia dilates blood vessels. NICE recommends starting active warming at least 30 minutes before induction when the patient's temperature is 36.0°C or above.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/inadvertent-perioperative-hypothermia-guidelineshttps://www.heatjac.com/knowledge/inadvertent-perioperative-hypothermia-guidelinesThu, 30 Jul 2026 12:40:00 GMTThe three most cited sources agree on the core idea: keep surgical patients at or above 36.0°C. NICE CG65 gives the most specific protocol, including 30 minutes of prewarming and 30-minute intraoperative checks. AORN's Guideline for Patient Temperature Management sets US nursing practice and favors active warming. The ASA standard requires temperature monitoring whenever clinically significant changes are expected.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/cooling-vests-for-surgeonshttps://www.heatjac.com/knowledge/cooling-vests-for-surgeonsWed, 29 Jul 2026 17:10:00 GMTCooling vests worn under surgical gowns can make surgeons noticeably more comfortable. In a 2023 randomized crossover trial of 30 orthopedic surgeons, an ice-pack vest cut thermal discomfort by 2.1 points on a 10-point scale and reduced perceived sweating and fatigue, without changing core temperature or cognitive test scores. Vests using ice or phase-change packs suit sterile attire best.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/cold-hospital-work-areashttps://www.heatjac.com/knowledge/cold-hospital-work-areasWed, 29 Jul 2026 12:20:00 GMTMany hospital areas outside the operating room run cold by design: interventional suites protect equipment and gowned staff, pharmacy cleanrooms control contamination, laboratories and storage areas protect specimens and medicines, and decedent care rooms are refrigerated. Staff in these areas stay warm by layering within each area's garbing rules, adding core warmth, limiting time in the coldest spaces and taking warm breaks.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/or-thermal-comfort-conflicthttps://www.heatjac.com/knowledge/or-thermal-comfort-conflictTue, 28 Jul 2026 17:09:00 GMTIn the same operating room, gowned surgeons working under lights often feel too warm while less active staff, especially anesthesia clinicians, feel cold. Studies using the ISO 7730 comfort method conclude that no single room temperature can satisfy every role. The most effective fixes are role-specific: cooling for scrubbed surgeons and added insulation or warmth for everyone else, within attire policy.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/cold-hands-and-surgical-dexterityhttps://www.heatjac.com/knowledge/cold-hands-and-surgical-dexterityTue, 28 Jul 2026 12:31:00 GMTCold reduces manual dexterity. A classic review set a finger skin temperature of about 15°C as a minimum for hand function, and newer work shows measurable losses can begin at warmer skin temperatures. Warming the hands, and the whole body, helps preserve performance. Operating rooms are not cold enough to reach those extremes for most staff, but cool, exposed hands can still feel clumsy.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/battery-devices-in-clinical-areashttps://www.heatjac.com/knowledge/battery-devices-in-clinical-areasMon, 27 Jul 2026 17:32:00 GMTPersonal battery devices such as phones, earbuds and heated vests are common in hospitals, but clinical areas add risks that homes do not. Operating rooms can have oxygen-enriched zones where any ignition source matters, and lithium-ion packs can overheat if damaged or charged improperly. Use certified products and approved chargers, clean devices before entering the OR, and follow your facility's electrical and fire safety policies.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/or-attire-infection-control-warm-layershttps://www.heatjac.com/knowledge/or-attire-infection-control-warm-layersMon, 27 Jul 2026 12:10:00 GMTAORN's surgical attire guideline allows a long-sleeve scrub jacket, or warm-up jacket, as part of surgical attire and says arms may be covered during patient skin antisepsis. It makes no recommendation on personal clothing under scrubs, leaving fabric and laundering rules to each facility. Scrub attire should be low linting and laundered at a health care-accredited laundry, per state rules, or per CDC recommendations.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/why-operating-rooms-are-coldhttps://www.heatjac.com/knowledge/why-operating-rooms-are-coldSat, 25 Jul 2026 23:52:35 GMTUS operating rooms are designed to ASHRAE/ASHE Standard 170, which sets a temperature of 68 to 75 °F (20 to 24 °C) and relative humidity of 20 to 60 percent. Many rooms run at the cool end mainly because surgeons wear gowns under hot lights, and humidity has to be managed alongside temperature. Cold air is not what keeps the room sterile.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/heat-reflective-liningshttps://www.heatjac.com/knowledge/heat-reflective-liningsSat, 25 Jul 2026 23:52:25 GMTA heat-reflective lining is a thin metallized layer that returns infrared energy from your body instead of absorbing and re-emitting it outward. It works because skin is a strong infrared emitter and radiation is the largest route of heat loss at rest, about 60 percent. It conserves heat you already make; it cannot create heat, block wind or stop conduction.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/raynauds-staying-warmhttps://www.heatjac.com/knowledge/raynauds-staying-warmSat, 25 Jul 2026 23:51:48 GMTTo stay warm with Raynaud's, keep your whole body warm, not just your hands. Dress in layers with a hat, wear gloves or mittens whenever you handle cold things or step into air conditioning, avoid sudden temperature changes, and carry warmers for long exposures. If an attack starts, move somewhere warm and run warm, not hot, water over your fingers.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/how-the-body-loses-heathttps://www.heatjac.com/knowledge/how-the-body-loses-heatSat, 25 Jul 2026 23:50:46 GMTThe body loses heat in four ways. Radiation sends infrared energy from skin to cooler surfaces nearby. Convection carries heat away in moving air or water. Conduction passes heat into anything cooler you touch. Evaporation removes heat as sweat and moisture turn to vapor. At rest in a cool room, radiation is the largest route, at about 60 percent.Science of WarmthThermal Sciencehttps://www.heatjac.com/knowledge/scrub-jacket-vs-warm-up-jacket-vs-vesthttps://www.heatjac.com/knowledge/scrub-jacket-vs-warm-up-jacket-vs-vestFri, 24 Jul 2026 17:07:00 GMTIn surgical settings, scrub jacket and warm-up jacket usually mean the same garment: a long-sleeve jacket worn over scrubs. It warms the arms and is widely accepted when clean and laundered per policy. A thermal vest warms the core with arms free. The warmest policy-friendly combination for most cold clinicians is a low-lint base layer, a thin core vest and a facility-laundered warm-up jacket.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/heated-vest-under-scrubshttps://www.heatjac.com/knowledge/heated-vest-under-scrubsFri, 24 Jul 2026 12:18:00 GMTYou can often wear a thin heated or thermal vest under scrubs, but whether it is allowed depends on your facility's policy for personal clothing, fabric and electrical devices. Passive insulated or heat-reflective vests and pockets for air-activated warmers raise the fewest questions. Battery-heated vests may need approval, especially in operating rooms, and every option should be clean, low-lint and comfortable against skin.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/how-to-stay-warm-in-the-operating-roomhttps://www.heatjac.com/knowledge/how-to-stay-warm-in-the-operating-roomThu, 23 Jul 2026 17:37:00 GMTTo stay warm in the operating room, layer from the skin out within your facility's attire policy: a close-fitting, low-lint base layer under scrubs, a clean warm-up jacket when arms may be covered, and added core warmth such as a thin vest. Cover your head and feet, keep moving between tasks, eat and hydrate, and ask about room temperature between cases.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/what-is-perioperative-hypothermiahttps://www.heatjac.com/knowledge/what-is-perioperative-hypothermiaThu, 23 Jul 2026 12:08:00 GMTPerioperative hypothermia is a core body temperature below 36.0°C (96.8°F) in the period around surgery. It is common because anesthesia impairs the body's temperature control and moves heat from the core to the skin, while patients lie exposed in a cool room. Even mild hypothermia is linked to more bleeding, wound infection, cardiac events and patient discomfort.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/thermal-gear-buying-guidehttps://www.heatjac.com/knowledge/thermal-gear-buying-guideWed, 22 Jul 2026 17:42:00 GMTA heated vest is a battery-powered garment with thin heating panels, usually over the back and chest, that adds warmth to your core on demand. Choosing well means matching the format to your use, sizing for your layers, comparing batteries in watt-hours, checking safety testing and recalls, and knowing when battery-free warmth from insulation, heat-reflective linings or air-activated warmers is the better tool.Technology and GearBuying and Carehttps://www.heatjac.com/knowledge/personal-cooling-guidehttps://www.heatjac.com/knowledge/personal-cooling-guideWed, 22 Jul 2026 12:28:00 GMTA cooling vest is a garment that draws heat away from the torso using evaporating water, ice, phase-change packs, or circulating liquid or air. Research shows cooling vests can lower skin temperature and make heat feel more tolerable, but they supplement rather than replace the basics of heat stress prevention: water, rest, shade, acclimatization and recognizing heat illness early.Heat and CoolingCooling and Heat Stresshttps://www.heatjac.com/knowledge/heatjac-origin-storyhttps://www.heatjac.com/knowledge/heatjac-origin-storyWed, 22 Jul 2026 12:04:49 GMTHEATJAC was developed through years of research, testing, material exploration, and product refinement to address real-world thermal challenges across demanding environments.It All Begins HereTechnology and GearWarming Technologieshttps://www.heatjac.com/knowledge/temperature-control-and-the-next-evolution-of-thermal-technologyhttps://www.heatjac.com/knowledge/temperature-control-and-the-next-evolution-of-thermal-technologyWed, 22 Jul 2026 12:02:58 GMTRead how we're building the technology, systems, and IP leading the next generation of intelligent thermal performance, for how real people move every day.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/staying-warm-guidehttps://www.heatjac.com/knowledge/staying-warm-guideTue, 21 Jul 2026 17:11:00 GMTThe best way to stay warm outside is to layer: a wicking base layer, an insulating mid layer and a wind- and water-resistant shell, plus a hat, mittens and warm socks. Stay dry by venting before you sweat, block wind, insulate yourself from cold ground, and eat and drink regularly. Indoors, keep living spaces warm, especially for older adults, and use heaters and heated products carefully.Everyday Life and HealthOutdoor and Everydayhttps://www.heatjac.com/knowledge/cold-readiness-guidehttps://www.heatjac.com/knowledge/cold-readiness-guideTue, 21 Jul 2026 12:39:00 GMTCold-weather readiness means solving two thermal problems at once: keeping the team warm, dry and able to use their hands, and keeping casualties from losing heat. Military practice relies on adjustable layering such as the Army's seven-level ECWCS, strict moisture control to avoid cold injuries, and casualty warming kits like the HPMK. Batteries, body armor and procurement rules shape every choice.Work and DutyMilitary and EMShttps://www.heatjac.com/knowledge/cold-work-guidehttps://www.heatjac.com/knowledge/cold-work-guideMon, 20 Jul 2026 17:09:00 GMTCold stress happens when the body loses heat faster than it can replace it, cooling the skin, the hands and feet, and eventually the core. Low temperature, wind and wetness all drive it. In the United States OSHA has no specific cold standard, so employers manage the hazard under the General Duty Clause with engineering controls, warm-up breaks, training and suitable clothing.Work and DutyWorkplace Coldhttps://www.heatjac.com/knowledge/cold-sensitivity-guidehttps://www.heatjac.com/knowledge/cold-sensitivity-guideMon, 20 Jul 2026 12:08:00 GMTFeeling colder than the people around you is common and often harmless, but it can also point to Raynaud's phenomenon, an underactive thyroid, anemia or nerve changes. A practical plan has two parts: notice the pattern of your symptoms so a clinician can look for a cause, and build a warmth routine that keeps your whole body, especially your core, comfortably warm.Everyday Life and HealthCold Sensitivityhttps://www.heatjac.com/knowledge/clinician-thermal-comfort-guidehttps://www.heatjac.com/knowledge/clinician-thermal-comfort-guideFri, 17 Jul 2026 17:46:00 GMTOperating rooms are designed to run between 68°F and 75°F (20°C to 24°C), and many sit near the cool end to protect gowned surgeons and control humidity. That leaves circulating nurses, anesthesia staff and other less active team members cold. The practical answer is layered, policy-compliant attire: a clean warm-up jacket, a low-lint under layer and added core warmth, all within your facility's attire and device rules.HealthcareClinician Comforthttps://www.heatjac.com/knowledge/perioperative-warming-guidehttps://www.heatjac.com/knowledge/perioperative-warming-guideFri, 17 Jul 2026 12:30:00 GMTPatient warming is the set of practices that keep surgical patients at or above 36.0°C, the threshold for perioperative hypothermia. Anesthesia disables normal temperature control and operating rooms are cool, so most patients lose heat without help. Effective programs combine prewarming, active warming with forced-air or conductive devices, warmed fluids, sensible room settings and accurate core temperature monitoring.HealthcareClinical Warminghttps://www.heatjac.com/knowledge/warming-technologies-guidehttps://www.heatjac.com/knowledge/warming-technologies-guideThu, 16 Jul 2026 17:14:00 GMTEvery warming technology does one of two things: it adds heat to the body or it slows the heat the body loses. Chemical warmers and battery heaters add heat. Insulation, heat-reflective linings, space blankets and aerogel slow loss. Phase-change fabrics only store and return heat briefly, and far-infrared textiles only redirect it. The warmest systems combine a heat source with insulation and reflection.Technology and GearWarming Technologieshttps://www.heatjac.com/knowledge/thermal-science-guidehttps://www.heatjac.com/knowledge/thermal-science-guideThu, 16 Jul 2026 12:25:00 GMTThe body stays warm by balancing heat production against heat loss. Metabolism generates heat continuously, and the hypothalamus defends a core temperature of about 37°C by narrowing skin blood vessels and, if needed, triggering shivering. Clothing helps by trapping still air and slowing the four routes of heat loss: radiation, conduction, convection and evaporation. Wind, water and cold surfaces speed those losses.Science of WarmthThermal Science