Within the steel and metal processing industry, the EN ISO 11611 norm specifies the minimum safety requirements for protective clothing for welding and allied processes. Protective clothing that meets this norm keeps the wearer safe against molten metal sparks and accidental flame contact. Special welding operations require an extra measure of protection (more on this later).
Which FR risks does EN ISO 11611 cover?
The EN ISO 11611 standard consists of several tests, each of which simulates a different welding related risk or welding class. It’s also important to note that EN ISO 11611 is segmented into two classes. If the protective fabric passes all tests, it’s certified as EN ISO 11611 Class 1. If the fabric also passes the Class 2 requirements for the radiant heat, tear strength and molten metal tests, it’s certified as EN ISO 11611 Class 2.
Below are the specific requirements for each test:
1. Heat transfer, or radiant heat (ISO 6942)
• Class 1: 24 °C temperature increase after 7 seconds
• Class 2: 24 °C temperature increase after 16 seconds
2. Impact of molten metal spatter (ISO 9150)
• Class 1: 40 °C temperature increase after 15 droplets
• Class 2: 40 °C temperature increase after 25 droplets
3. Flame spread (ISO 15025)
• Code letter A1 - 10s surface ignition (required)
• Code letter A2 - 10s edge ignition (optional)
4. Electrical resistance (EN 1149-2)
• Should be higher than 105 Ω
5. Tear strength (ISO 13937-2)
• Class 1: minimum 15N
• Class 2: minimum 20N
REALITY CHECK: EN ISO 11611 IN THEORY VS PRACTICE
While they’re trustworthy safety standards set by experts, norms like EN ISO 11611 don’t always tell you everything about how to best protect your workers.
2. Over- and undergarments
Are you aware of the fact that the over- or undergarments that your workers wear in combination with their FR protective clothing can have an effect on the level of protection? Do you know about the dangerous situations that can occur when one of your workers wears the wrong layers underneath their FR garment? For instance, if a molten metal spatter burns through the coverall (or jacket) or enters through the sleeve, a 100% polyester or nylon undergarment can melt/drip on the skin — something you want to avoid at all cost!
3. Grinding resistance vs. welding sparks
The norm protects against hazards within “welding and allied processes”, but this is quite a broad term that might miss nuances specific to your work stations. Grinding resistance, for instance, is a different hazard from molten metal spatters. Although EN ISO 11611 is the right standard to meet if you are exposed to grinding risks, it doesn’t concretely specify how it protects against grinding resistance. Are you sure that you’re providing your workers with the best protective fabric for grinding risks? A field test at your workstation is an excellent way to perform a real-life check on how the fabric performs.
4. Contact with lubricants
Your workers are contaminated with lubricants on a daily basis, but are you aware of the effect of lubricant build-up on their protective clothing? It can have a negative effect on the flame resistant properties of the garments, so it’s smart to launder them regularly.