EN ISO 11612

Clothing to protect against heat and flame

Protective clothing for workers exposed to heat and flames (not including welders and firefighters). This means that the wearer is protected against brief contact with a flame and against (a limited amount of) convective and radiant heat. EN ISO 11612 superseded the older, now-withdrawn EN 531 standard.

Fabrics with this certificate

ScopeHeat & flame protection

ExcludesWelding · Firefighting

ReplacesEN 531

Code lettersA1/A2 + B · C · D · E · F

The contents of this standard

The pictogram is given above. This standard has a number of fabric tests. The results of the tests are represented by the letters A, B, C, D, E and F. If a letter is not specified, or if a class is given as “0”, the corresponding lowest test value has not been attained, or the corresponding test has not been carried out (which means the clothing does not have the respective protective properties).

Different tests, codes

Six test groups. Classes rise with performance.

Code letter · classes

Test setup & description

Test method

A · Flame spread

A1Surface ignition

A2Edge ignition

This test consists of applying a flame to a fabric sample for 10 seconds. To pass the test, the after flame & smoulder times and formation of holes must be within the tolerances (set in the standard). The application of a flame can take place in two ways:

ISO 15025

B · Convective heat

B14 < 10 seconds

B210 < 20 seconds

B321 seconds and longer

Convective heat: determination of the heat transmission when exposed to flames. The sample is held above the flame and the rise in temperature on the topside of the sample is measured with a calorimeter. Subsequently, the length of time the sample can remain exposed before its temperature rises by 24 °C is determined.

ISO 9151

C · Radiant heat

C17 < 20 seconds

C220 < 50 seconds

C350 < 95 seconds

C495 seconds and longer

Exposure to radiant heat. In this test, a fabric sample is exposed to radiant heat (infrared rays). The temperature on the reverse (unexposed) side of the sample is registered using a calorimeter. Subsequently, the length of time the sample can remain exposed before its temperature rises by 24 °C is measured. The test procedure is the same as EN ISO 11611, but the classification is different:

ISO 6942

D / E · Molten metal splash

D1Aluminium 100 < 200 grams

D2Aluminium 200 < 350 grams

D3Aluminium 350 grams and more

E1Iron 60 < 120 grams

E2Iron 120 < 200 grams

E3Iron 200 grams and more

Sequentially rising quantities of molten metal (for the D value – molten aluminium and for the E value – molten iron) are splashed on the sample. The quantity of molten metal which deforms the membrane is determined.

ISO 9185

F · Contact heat

F15 < 10 seconds

F210 < 15 seconds

F315 seconds and longer

This test method for the determination of contact heat transmission. It is applicable to protective clothing.

ISO 12127

Rain (optional)

WnnWaterproofing / vapour permeability

Optional test for protection against rain. The first “n” refers to the waterproofing class, the second “n” to the water vapour permeability class (see EN 343 for explanation).

EN 343

The requirements set in this standard

The respective clothing must always comply with the flame spread code A1 or A2 and at least 1 of the other codes (B to F). The label must indicate the class that the fabric has attained. XM FireLine fabrics are tested and documented against the full A–F range so the right combination can be certified for your garment.