EN ISO 11611: What you should know about this welding safety standard

With so many safety standards in the steel and metal industry, it can be challenging to find out which standards actually apply to you. In this blog, we take a deep-dive look at EN ISO 11611, the safety standard specifically related to protective clothing for welding and allied processes. What kind of protection does it guarantee? And which other variables have an effect on the level of protection your EN ISO 11611 certified protective clothing provides?

Within the steel and metal processing industry, the EN ISO 11611 standard specifies the minimum safety requirements for protective clothing for welding and allied processes. Protective clothing that meets this standard 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.

As a Health & Safety professional, you want your workers to be well protected in every possible situation, right? Even if you’ve passed the EN ISO 11611 tests, you’ll still need to take several additional factors into account: the specific class of certification you need, the type of garments you need, exposure to grinding resistance in your work station, and contact with lubricants.

1. Class 1 or Class 2?

Are you aware which class you need for your specific welding activities? Gas welding, for example, is a class 1 welding activity, while MMA welding, MAG welding (with basic or cellulose-covered electrode) and MIG welding (with high current) are class 2 welding activities. Your work environment can also affect which class you need. either class 1 or 2. For example, operating cutting machines (oxygen and plasma) or bench welding falls under class 1, while operating in confined spaces or overhead welding/cutting in constrained positions is class 2.

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 standard 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.

One standard, many variables to consider

Once you meet the EN ISO 11611 safety standard, you’ll gain peace of mind knowing that your workers’ protective clothing passes the basic heat and flame requirements for welding and allied processes. Beyond the basics, however, it’s also important to keep an eye on the additional variables which affect how protected your workers actually are in their specific work environment.