Scrub jacket, warm-up jacket or thermal vest: which keeps clinicians warmest?
In 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.
Is a scrub jacket the same as a warm-up jacket?
Mostly, yes. AORN's 2024 summary of its surgical attire guidance describes attire as a scrub top, pants or dress, with or without a long-sleeve scrub jacket, also known as a warm-up jacket. In hospitals the terms are used interchangeably for a snap-front or zip-front jacket in scrub-style fabric.
The practical difference is who owns and launders it. A facility-issued warm-up jacket goes through the hospital's laundry with other scrub attire. A personal scrub jacket bought from a uniform retailer is often washed at home, which may or may not meet your facility's policy for restricted areas.
How do the main options compare?
Each layer warms a different part of the body and raises different policy questions.
| Layer | What it warms | Typical policy status | Main tradeoff |
|---|---|---|---|
| Facility warm-up jacket | Arms and upper body | Widely accepted in restricted areas | Thin fabric, modest warmth |
| Personal scrub jacket | Arms and upper body | Varies; home laundering may not be allowed | Fit and style, laundering rules |
| Fleece jacket | Arms and upper body | Often restricted in the OR | Warm but may shed fibers |
| Thermal vest under scrubs | Core | Depends on personal clothing policy | Arms stay uncovered |
| Long-sleeve base layer | Arms and core | Depends on how much may show | Adds warmth with little bulk |
Why does fabric matter so much in the OR?
AORN recommends tightly woven, low-linting fabrics for scrub attire. The 2019 guideline cites research showing that tightly woven attire reduced bacterial contamination compared with conventional weaves. Fleece and loose knits are warm precisely because they are lofty, but that loft can shed fibers, which is why many facilities do not allow them in restricted areas.
The same logic applies to anything you wear under scrubs. AORN made no recommendation on personal clothing under scrub attire and asked facilities to set policies on fabric type and laundering, so check your local rules before choosing a fleece-lined base layer.
Do jackets actually reduce infection risk?
The evidence is unsettled, and AORN says so. The 2019 guideline states that arms may be covered during preoperative patient skin antisepsis, and it made no recommendation for long sleeves at other times. It cited one analysis in which requiring cover jackets added about $1,000 per month in laundry costs without a statistically significant change in surgical site infections.
For staff warmth, this matters because many facilities treat the jacket as optional rather than required. If a jacket is optional, a vest or base layer may be an equally acceptable way to stay warm.
Which option keeps you warmest?
Warmth depends on how much of the body a layer covers and how well it traps or returns heat. A jacket covers the arms, which lose heat readily and sit near cold air. A vest covers the torso, where the body works hardest to protect core temperature. OSHA's cold stress guidance explains that as the body cools it shifts blood flow toward the core, which is why a warm torso helps keep hands warmer.
Research on OR comfort supports adding sleeves for cold staff. A Belgian study in Building and Environment reported that nurses felt cold and that longer-sleeved clothing could improve their comfort. A 2026 model-based study recommended enhanced insulation for anesthesiologists while surgeons needed cooling, underlining that the answer depends on role.
For most cold clinicians, the combination beats any single garment: a thin base layer, a core vest, and a jacket that goes on when arms may be covered.
Which layer suits which role?
Use these starting points and adjust to your room and policy.
Anesthesia clinician at the head of the table: core vest plus warm-up jacket, since low activity and airflow make this spot cold.
Circulating nurse: base layer plus jacket, with a thin vest for colder rooms or long cases.
Scrubbed technologist or surgeon: base layer only under the gown, since sterile gowns trap heat.
Preoperative and recovery staff: jacket or vest depending on unit dress code and patient contact.
What to look for when buying
Choose a tightly woven, low-lint outer fabric, snaps or zips that close cleanly, and cuffs that stay out of the way during hand hygiene. For a vest, look for a low profile that fits under the scrub top, and check the care label against your facility's laundering method. If you feel cold even in rooms colleagues find comfortable, or notice color changes in your fingers, talk to a clinician about those symptoms.
Key takeaways
Scrub jacket and warm-up jacket usually describe the same long-sleeve garment worn over scrubs.
Fabric and laundering rules, not warmth, decide what is allowed in restricted areas.
A jacket warms the arms; a vest warms the core; combining them works best for most cold staff.
AORN leaves long sleeves outside skin antisepsis and personal under layers to facility policy.
Frequently asked questions
What is a warm-up jacket in nursing?
It is a long-sleeve jacket worn over scrubs to keep the arms warm, often with snaps or a zipper. AORN refers to it as a long-sleeve scrub jacket, also known as a warm-up jacket.
Can I wear a fleece jacket in the operating room?
Many facilities do not allow fleece in restricted areas because lofty fabrics can shed fibers. AORN recommends tightly woven, low-linting fabrics for scrub attire, so check your policy.
Do I have to wear a jacket in the OR?
AORN states that arms may be covered during preoperative patient skin antisepsis and made no recommendation on long sleeves at other times. Your facility's policy decides whether a jacket is required.
Is a vest or a jacket warmer for scrubs?
A vest keeps the core warm, which helps the hands stay warmer, while a jacket covers the arms. Most cold clinicians get the best results by combining a thin vest with a jacket.
Can I wash my scrub jacket at home?
AORN recommends laundering scrub attire at a health care-accredited laundry, according to state rules, or according to CDC recommendations. Some facilities allow home laundering for certain areas, so follow your local policy.
Related reading
Sources
Surgical Attire, Stethoscopes and Personal Items, AORN Periop Today
Thermal comfort of the surgical staff in the operating room, Building and Environment, 2014
One Operating Room, Two Thermal Worlds: Determinants and Limits of Thermal Comfort for Surgical Staff, Atmosphere (MDPI), 2026
Cold Stress Guide, Occupational Safety and Health Administration
About HEATJAC. HEATJAC is a thermal architecture company founded by an anesthesiologist. We design patented garment systems that capture, conduct and broaden warmth across the body, and we publish this knowledge hub because the science of staying warm should be public. HEATJAC products are not medical devices and are not intended to diagnose, treat, cure or prevent any disease.