FR Base Layers
Most FR workwear programs start at the outer layer. That's too late.
When arc flash or flash fire occurs, non-FR synthetic base layers — polyester, nylon, spandex — melt against skin, turning a survivable incident into a catastrophic burn injury even when the outer FR garment does its job perfectly. The fix is simple and it starts here.
Rasco FR base layers are built from 5 oz FR modacrylic blend — inherently flame resistant, lightweight, and moisture-wicking — in a performance athletic fit that moves with your body rather than bunching under your gear. This isn't camping base layer. It isn't hiking underwear. It's engineered for the job site: slim enough to disappear under your work shirt, protective enough to matter at the skin level, breathable enough to actually prevent heat exhaustion on a 95-degree shift.
With a 6 cal/cm² arc rating (ATPV) — CAT 1, meets ASTM F1506, every layer in your FR system is now working for you — from skin to outer shell.
Choose your base layer:
FR Short Sleeve Base Layer — $76
Maximum breathability. The hot-weather choice for electrical crews, oilfield workers, and anyone working in summer heat who still needs FR from skin out. Pairs under any FR shirt, coverall, or henley.
FR Long Sleeve Base Layer — $88
Full arm coverage. The cold weather layering choice and the year-round option for workers who need FR coverage from wrist to collar at all times. Orange version available for crews with hi-vis visibility requirements.
Why FR modacrylic?
FR cotton is heavy. FR synthetics without the FR treatment melt. Modacrylic is the base layer fiber of choice because it's inherently flame resistant — the protection is in the fiber, not a treatment that washes out — and at 5 oz it's dramatically lighter than FR cotton knit. It wicks moisture the way performance athletic wear does, which is what actually prevents heat exhaustion on long shifts in the sun.
The athletic fit matters too. Traditional base layers run relaxed — they bunch under your work shirt and create pressure points through a 10-hour shift. Rasco's base layers are cut for movement: close to the body, flatlock seams that don't irritate skin, tagless construction. You wear it all day and forget it's there until it matters.
Build your complete FR system:
FR Base Layer (6 cal) → FR Henley or Uniform Shirt (8–10 cal) → FR Hoodie (22 cal) → FR Canvas Jacket (38 cal CAT 3)
Every layer rated. Every layer doing its job.
Want more weight and coverage?
For workers who prefer a heavier FR layer against the skin or want a standalone FR shirt with more substantial fabric:
- FR Henley (Men's) — 7 oz FR cotton, 8.7 cal CAT 2, $65
- FR Women's Henley — 8.7 cal CAT 2, women's cut, $75
- FR Long Sleeve T-Shirt — 7 oz FR cotton, standalone or layering option
