Protection against electric arc
Arc ... a danger that all electrical installation may be related
The invention of the fluorescent lamp and arc welding are two positive effects of the natural phenomenon "arc", also called electric arc or arc. When, however, the arc of control is created, then this is a dangerous phenomenon with body and injuries often result in death.
The danger lies not only in the extreme heat (up to 30,000 degrees Celsius) and hot metal splashes, but also in the transfer of heat, toxic copper vapor gases, heavy smoke, sound above 140dB, explosive busy flying metal splinters, UV and IR light, fire hazards and possible electrocution.
Emergence of an arc
Electric arc is caused when an electrical charge is passed between two electrodes. A plasma is formed. Then, the light gas between the electrodes.
An arc occurs in 80% of cases after human error. When working on the electrical tools sometimes slip out of the hands of maintenance staff and these tools are to live parts of an installation or the insulation is damaged or broken conductor.
Preventing arc risks
The best remedy is always avoid a hazard. Only then, the following mandatory steps taken in dealing with possible arc:
Protect your plants: here the focus was always on in the past
Raise awareness about the risks that can not be avoided
Turn the power off if possible
Protect yourself with appropriate PPE when the power supply can not be switched off
Protective workwear and PPE arcing
We now know what hazards exist, but the statistics on injured body parts also gives insights about which PBMs are most important. In particular, the hands being injured (50-70%), the forearm (30-50%), the head (50%) and the rest of the body is around 10%. Respiratory protection is required.
Hand and forearm protection must meet the requirements stated in IEC EN 60903. Safety Workwear Shop recommends to use because it will melt in arc and no rubber gloves, then NEVER prevent burning. So Safety Workwear Shop also recommends only two types of gloves:
IsoArc: flexible and less mechanical protective gloves Honeywell
Composite gloves: slightly stiffer and more mechanical protective gloves Honeywell
Head and face protection can best be combined by applying a helmet that complies with EN 50365 (head protection) and EN 166 part 8 and EN 170 UV eye protection.
Workwear should meet at different levels and in line with European norms:
Protection against lasgevaren: EN ISO 11611 Class 1-A1
Flame protection: EN ISO 11612 A1, B1, C1, F1
Protection against thermal effects of arc: EN ISO 61482-1-2 Class 1 and Class 2 (Article 2220)
No short sleeves!
The third standard requires disclosure. In Europe, one uses a Box-test in a closed laboratory setting while the U.S. standard NFPA70E provides a openluchtest, namely the ATPV (Arc Thermal Performance Value). In the explosion test, the box facing the clothing and tested in the test, the ATPV explosion in all directions. The second difference is that the entire garment box test test includes push buttons and pockets test than the test ATPV a piece of material of a garment is tested. The ATPV test measured only the radiant heat and the Box-test the garment tested for radiant heat and convection heat and also released Plasma. Indeed, the latter focuses much damage to the clothes which are still unexpected heat contact with the skin may occur through cracks.
Types of clothing: Flame retardant underwear cotton or Nomex material which does not melt by the enormous heat, FR shirt, multi-standard work pants, multi-standard, multi-standard work vest or coveralls.
For more information about solutions for Safety Workwear Shop, please contact Tom Buyens on +32 468 20 67 58 or [email protected]