Welding

Protective clothing during welding or similar operations

(EN/ISO 11611 cancels and replaces EN 470-1:1995 and EN 470-1:1995/A1:1998)

The clothing is intended to protect the user against small splashes of molten metal (EN348), short contact time with flame (EN532), and ultra violet radiation, and to be worn continuously for up to 8 hours at ambient temperature.

This standard specifies the requirements for clothing worn during welding operations. This clothing can be worn at normal temperatures for an entire working day (8 hours) and it provides protection against small spatters of molten metal, incidental flame contact and UV radiation. This particular standard does not cover protective clothing worn for special types of welding. The contents of this standard This standard consists of a series of tests, the most important of which are described in ISO 6942, ISO 9150, ISO 15025 and EN 1149-2. ISO 11611 has two classes. If the fabric passes all the tests, it is designated as Class 1. If the fabric receives a Class-2 rating for the ISO 6942 and ISO 9150 tests, it is designated as Class 2.Different tests ISO 6942 This is a test method for assessing fabrics and fabric combinations exposed 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 the sample can remain exposed before its temperature rises by 24 0C is measured. This test is also used for EN 531C and has two different classes: Class 1 temperature increase occurs after ≥ 7 seconds Class 2 temperature increase occurs after ≥ 16 seconds.ISO 9150 Determining the behaviour of fabrics when exposed to small spatters of molten metal. In this test, droplets of molten metal are spattered on a vertically suspended fabric sample. Subsequently, the number of droplets it takes to cause an increase in temperature of 40 °C on the reverse side of the sample is determined. This test also has two classes: Class 1 ≥ 15 droplets of molten metal Class 2 ≥ 25 droplets of molten metal.ISO 15025 Test method for limited flame spread. The 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). This test is also used for EN 531A. The application of a flame can take place in two ways: in procedure A (leads to Class A1), the flame is applied horizontally (similarly to EN 470 and EN 531) in procedure B (leads to Class A2), the flame is applied laterally.The requirements set in this standard Clothing that complies with this standard must always meet the requirements stipulated in ISO 13688: 1998. Protective clothing — General requirements. Exterior pockets must have a flap that is 10 mm wider than the actual pocket on both sides This does not include trouser leg pockets that are placed behind the side seam and that have an opening of 75mm or less (for pocket meters) Vertical pockets under the hips placed at an angle of 10 degrees or less are not required to have a flap Side access openings must always have a flap or hook-and-loop fastener, even if they are placed vertically Metal fastenings must be covered on the inside or outside Pleats, etc. must be avoided Neck openings must be closed Maximum distance between buttons 15cm. Changes compared to EN 470-1:1995/A1:1998 The pictogram has been changed (previously a flame, now a welding arc) The flame spread must also be determined after a maximum number of washes. In general, fabric performance after 50 washes is tested (Much) higher requirements are set for the fabric’s tear strength Specific requirements for models are also set for seam strength and flame retardancy Sundries must also be tested for heat resistance At the present time, this standard is separated into two classes with subdivisions according to the type of work the fabric is designed to withstand. See table:

Criteria for choice on the basis of the type of process		Criteria for choice on the basis of the type of work
CLASS 1		CLASS 1
Manual welding operations during which small amounts of spatter or droplets of molten metal are formed – Gas welding – TIG welding – MIG welding – Micro plasma welding – Soldering brass – Spot welding – Shielded electrode MMA welding		Operating machines, e.g. – Oxygen cutting machines – Plasma cutting machines – Resistance pressure welding machines – Thermal spraying – Welding tables
CLASS 2		CLASS 2
Manual welding operations during which large amounts of spatter or droplets of molten metal are formed, e.g.: – MMA welding (using alkaline or cellulose electrodes) – MAG welding (with CO2 or mixed gasses) – MIG (high-voltage) welding – Flux-cored arc welding – Plasma cutting – Gouging – Oxygen cutting – Thermal spraying		Operating machines, e.g.: – In enclosed spaces – When welding/cutting operations require reaching above head height or take place in comparable difficult positions

ISO 11611 cancels and replaces EN 470-1:1995 and EN 470-1:1995/A1:1998, which have been technically revised to:

a) Includes additional clothing in the scope;
b) Specifies two classes of protective clothing;
c) includes additional terms and definitions;
d) Specifies ageing due to washing (maximum number of cleaning procedures as indicated by the manufacturer);
e) Specifies additional tests for heat transfer (radiation) and electrical resistance;
f) Specifies requirements for innocuousness;
g) Modifies requirements for dimensional change on washing to include requirements for knitted fabrics;
h) Deletes test method for the thickness of leather;
i) modify requirements for tensile strength and tear strength;
j) Specifies requirements for burst strength and seam strength;
k) Includes test procedure for the flame testing of seams and hemmed edges;
l) Modifies the information to be supplied by the manufacturer;
m) Specifies requirements for care and maintenance;
n) Includes annex for the selection of welders’ clothing;
o) Includes annex regarding information on UV radiation hazards;
p) Includes annex for uncertainty of measurement.