These lightweight flame resistant trousers are for work involving heat, flame and electric arc risks, including ATEX environments. Stretch panels in key movement areas and a stretch crotch gusset let you bend, kneel and climb with ease throughout the shift.
Eight pockets give you room for phones, pens and tools, with thigh pockets for secure storage and two tier knee pad pockets for adjustable knee protection. An extendable leg and side elastic waist help you get a comfortable, practical fit.
Key features
- Stretch panelling in key movement areas gives flexibility in all working positions
- Stretch crotch gusset adds flexibility and reduces stress on the seams
- Two tier knee pad pockets let you set knee pads at two heights
- Eight pockets, including an easy access cargo pocket, rule pocket, multi-functional thigh pockets and two back pockets
- Extendable leg length from 31″ to 33″ lets you adjust the length to suit
- Side elastic waist for a comfortable hold at the waist
- Metal detector friendly: non-magnetic, nickel and ferrous free
- UPF 40+ rated fabric blocks 98% of UV rays when working outdoors
- Sewn-on flame resistant industrial wash tape
Materials and performance
Shell: Bizflame Work, 99% cotton, 1% carbon fibre, 210g. Contrast panels: Bizflame Work Stretch, 97% cotton, 2% elastane, 1% carbon fibre.
Standards and protection
Certified to EN ISO 11612 (A1+A2, B1, C1, E2, F1) for protection against radiant, convective and contact heat, EN ISO 11611 Class 1 (A1+A2), EN 1149-5 and EN 61482-2 / EN 61482-1-1 (ELIM 9 CAL/CM², ATPV 9.4 CAL/CM²). These trousers are CE Category III PPE.
Fit and sizing
Regular fit. See our Portwest Sizing Guide for detailed information.
Knee protection
The two tier knee pad pockets give you two positioning options, so you can set your knee pads where they best suit your height and the way you kneel.
Care
- Machine wash at 60°C
- Do not bleach
- Tumble dry at low temperature
- Iron at a medium temperature (max 150°C)
- Do not dry clean
Add your logo
If you’d like to add your logo to the Portwest FR401 Bizflame Work Lightweight Stretch Panelled FR Trousers, please contact us.


































