Forests primarily burn during summer; the fires last many hours. Radiant heat can be elevated. The standard helps to prevent that the fire fighter develops too high levels of metabolic heat. Therefore his protective clothing must be light and effective, without introducing heat stress to the wearer.
Paragraph 4 of this norm describes the design of the suit. A few examples:
- Fastening systems to avoid the penatration of burning residues
- The collar has to remain upright
- No cuffs in tricot
- A fastening system that bridges the border of the trousers and the boots
- Sleeves with fastening system.
Paragraph 5 prescribes that the garment has to be washed (at least 5 times) according to the instructions of the manufacturer before certification.
The radiant heat test is defined in paragraph 6.3 by the EN ISO 6942: 2002 with a heat flux of 20kW/m².
The fabric or the assembly has to present an RHTI24 that is higher than 11 seconds with a RHTI24-RHTI12 differential of more than 4 seconds.
In addition all the components such as badges and fasteners are tested for 5 minutes at a temperature of 180°C according to the ISO 17493.
The sewing thread can't melt at a temperature of 260°C.
The fabrics and the confection also have to respect several mechanical criteria:
- The outer fabric has to present a tensile strength that is higher than 450 N according to the ISO 13934-1 and a tear strength of more than 20 N (ISO 13937-2).
- The principal seams also have to offer a resistance of at least 225 N (ISO 13935-2).
What's more, to guarantee an excellent comfort, the fabric or the assembly has to have a thermal resistance of ≤0,055 m².K/W (EN31092) and a water vapour resistance of ≤ 10m².Pa/W (EN31092) for a good breathability.
Finally, the garment has to present at least 0,13m² of retroreflective material (EN 471) or at least 0,2 m² if the material has combined characteristics.