💥 The sparks 💥 fly What does modern welding protective clothing have to do?

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💥 protective clothing for welding and related processes 💥 (ISO 11611:2015); German version EN ISO 11611:2015

Protective clothing is mandatory for welding and any related process. EN ISO 11611:2015 summarises the essential protection requirements and has replaced the old EN 470-1 standard. Welding clothing has 2 performance classes. Protection class 1 and protection class 2. Protection class 2 corresponds to the higher performance level.

1. Safety professional tip for welding protective clothing 💥

The protection of the respiratory tract, feet, hands, face and eyes is not taken into account in this directive. However, welding clothing alone is not sufficient to protect the employee.

What does welding clothing protect against? 💥

  • Thermal radiation (ISO 6942)
  • Smallest, liquid metal splashes (ISO 9150)
  • Short-term contact with fire (ISO 15025)
  • Electric shock (limited) (ISO 1149-2)

2. Protection professional tip for welding clothing 💥

Protective welding clothing is suitable for fleeting contact with small flames, but does not protect against flames or great heat. Flame-retardant means that the welding clothing does not burn off over a large area.
It is also not an electrically insulating protective clothing, it reduces the risk of electric shock, which occurs during a short voltage contact, up to 100 volts under normal welding conditions.

Why are there two protection classes? 💥

The welding process and the workplace environment determine the health insurance fund in the risk assessment.

Hazard due to the type of welding process
  • Protection class 1
    e.g. gas fusion welding, TIG welding, MIG welding (with low current), microplasma welding, brazing, spot welding, MIG welding (with low current), MMA welding (with a rutile-coated electrode).
  • Protection class 2
    e.g. MMA welding (with alkaline or cellulose-coated electrode), MAG welding (with CO2 or mixed gases), MIG welding (with high-voltage current), self-protective cored wire arc welding, plasma cutting, gouging, oxygen cutting, thermal spray welding.
Exposure to workplace conditions
  • Protection class 1
    e.g. oxygen cutting machines, plasma cutting machines, resistance welding machines, machines for thermal spray welding, table welding.
  • Protection class 2
    e.g. confined spaces, overhead welding or cutting, working in forced postures.

Why does DIN EN ISO 11611:2015-1 combine so many standards? 💥

Only the interaction of the material, the seams, the sewing thread, the workmanship and the design offers protection against liquid metal splashes, short-term contact with fire and radiant heat. The protective clothing consists of a wide variety of materials, all of which must be standardised and tested accordingly.

Which standards are summarized under DIN EN ISO 11611:2015-1?

The general requirements that are not specifically covered by ISO 11611:2015 must be compliant with ISO 13688. (link to ISO 13688).

The following performance parameters are used for classification 💥

Heat transfer or radiant heat (DIN EN ISO 6942)
  • Class 1: Temperature rises by 24 °C after 7 seconds RHTI > 7 s
  • Class 2: Temperature rises by 24 °C after 16 seconds RHTI > 16 s

RHTI (radiant heat transfer index). Is the measured time at which a temperature increase of 24 °C is achieved by radiant heat on the back of the material and thus also on the skin.

Exposure to metal splashes (ISO 9150)
  • Class 1: Temperature rises by 40 °C after 15 drops
  • Class 2: Temperature rises by 40 °C after 25 drops
Limited flame spread (DIN EN ISO 15025)
  • Code letter A1 – 10 sec. surface flame (required)
  • Code letter A2 – 10 sec. edge flame (optional)
Flame treatment of material and seam
  • A1 – Surface Flame
  • A2 – Edge Flame Coating
  • no further burning
  • No hole formation
  • No dripping
  • Afterburn time < 2 s
  • Afterglow time < 2 s Electrical resistance – contact resistance (DIN EN 1149-2) > 105 Ω (at 85% rel.
  • humidity)

Required Physical Properties 💥

Tear propagation resistance longitudinally and transversely (ISO 13937-2)
  • Class 1: at least 15 N
  • Class 2: at least 20 N
Tensile strength textile longitudinal and transverse (ISO 13934-1)

> 400 N

Seam strength (ISO 13935-2)

> 225 N

What does "good" or prescribed design mean in this context? 💥

The design ensures that the welding pants and jacket fit like a "good suit".
To keep it that way, the clothing must be dimensionally stable. Running-in is only allowed to a small extent.

Dimensional change in fabric 💥

Dimensional change in textile fabrics after pre-treatment < 3%
Dimensional change in knitted materials after pre-treatment < 5%)
The skin is completely covered, even when lying down or when the wearer moves. A mason's cleavage is passé for welding , it not only tortures the retina of your colleagues, a liquid metal splash burns itself into place immediately, no matter how fast you jump around or try to get the spark out of your pants. For this reason, welding clothing must not form any movement folds in which glowing metal splashes can settle.

3. Protection professional tip for welding protective clothing 💥

Important! Pay attention to flame-retardant underwear. Synthetic underwear burns like tinder. Plastic melts and burns into the skin. Another design plus for healthy skin is the flame-retardant material and the tear-resistant seams. The concealed pockets and a collar that protects the neck. The tensile strength of particularly stressed areas such as elbows or knees and the seam strength are also important. Each preset protects the skin from liquid metal splashes or burns.

Design Requirements for Welding Protective Clothing 💥

  • The distance between buttonholes/snaps is a maximum of 150 mm
  • Zippers completely close all openings and are concealed
  • All closures are concealed
  • Closures are wrinkle-free
  • The width of the cuff is on the underside
  • Cuffs are without turn-ups
  • The neck opening (collar) must be closed completely
  • Trousers and overalls are without turn-ups. Side slits are closable and concealed
  • All pockets are covered
  • Bag flaps are 2 cm wider than bags so that the bag flap does not fit in the bag
  • The angle of access for trouser pockets is a maximum of 10o
  • The pocket opening on overalls is straight
  • The ruler pocket behind the leg seam has an opening width of a maximum of 75 mm
  • The jacket must overlap the pants so far that a person with outstretched arms can bend forward until the fingertips touch the floor without creating a gap
  • Bridging between the outside and the inside of clothing, e.g. by metal fasteners that conduct heat or electricity, is prohibited!

Special case of grinding – cut-off grinding – flexing 💥

Although activities with grinding risks fall under EN ISO 11611, it does not specify what protection welding protective clothing offers during grinding. Because there is no standard for cut-off grinding or flexing. Without a standard, there is no corresponding test procedure.

Welding clothing is not really suitable for grinding, as the demands of cut-off grinding are special. Grinding is not a welding process. During grinding, metal, sometimes glowing, hits fabric at high speed and again and again. It's like shooting a cannon at the city wall. At some point, the wall gives way and gets holes. Intensive grinding actions wear out the clothing much faster and make it unusable for welding.