Electric arc

An electric arc is a powerful electrical discharge that can lead to life-threatening injuries. A lightning strike during a thunderstorm is an example of an electric arc. An electric arc causes thermal effects, loud noise, spatter, molten metal and can lead to, among other things, extensive burns.

To reduce the risks, preventive safety precautions must be taken for everyone working where an electric arc may occur.

Active protection against electric arcs

The following provide a good foundation for protecting against electric arcs:

Prevent
An analysis must be performed prior to all electrical work. Also make sure that everyone who will be handling the equipment in question has the experience and knowledge required.

Wear the right protective clothing
When working where there is a risk that electric arcs can be activated, the right clothing must always be worn. Electric arc clothing is a category III-garment under the PPE Regulation.

Wear protective clothing correctly
Wear flame- and electric arc-protected garments from your underwear to your outerwear. Also wear a helmet with an approved visor that provides electric arc protection and hearing protection, and is electrically insulated.

Protective equipment against electric arcs

Here you will find products that protect you against electric arcs.

Contact

Would you like more information on how to create a safer work environment or order a free risk analysis?

From risk analysis to follow-up

We help you conduct a risk analysis together with both safety representatives and users.

What is an electric arc?

An electric arc is a powerful electrical discharge that is transmitted between two current-carrying conductors through the air. The temperature of an electric arc may exceed 19,000°C at the source. For comparison, the temperature of the sun’s surface is approximately 6000°C.

What are the risks of an electric arc?

The explosion in connection with an electric arc can cause major injuries. The intensity can lead to burns, a loss of vision and hearing and other issues. It could even be fatal.

Strength of electric arcs

The strength of an arc is measured in cal/cm² (calories per square centimeter)
Examples of roughly what the measurements correspond to:

1 cal/cm² = Slowly moving your hand over a lighter or candle
3 cal/cm² = Sunburns, superficial effect on the skin
5 cal/cm² = Strong sunburn, area above 25% means hospitalization
8 cal/cm² = Serious burn. If the area is greater than 50%, the nerves of the skin are damaged, transplantation is necessary and the outcome could even be fatal.

Which sectors and occupational groups are most vulnerable?

Electricians
Industrial workers

Protecting yourself

Start by determining your equipment's electric arc classification. For more information on how to do this, read SSG4510 section 6 Calculation model of arc flash hazard.

Wear protective clothing that protects at least as much as a potential switchgear electric arc can generate in cal/cm². In such cases, an approved helmet with a visor that protects against electric arcs and electrically insulated hearing protection must be worn.

Rebuild the equipment if necessary.

An example of increased safety in the equipment is modern electric arc guards that cut the power in 20–30 milliseconds. There are also electric arc attenuators that supplement the arc guard and cut the current in only 2 milliseconds.

What does the law say?

When working on disconnected equipment, safety measures must be taken to ensure that the equipment remains disconnected and de-energized for the duration of the work.
When working on or in the vicinity of live equipment, safety measures must be taken to prevent those participating in the work being injured by electric shock, the effects of an electric arc or short circuit.

What is the employer’s responsibility?

Make sure that the correct protection is available with instructions for how to use it correctly at the workplace. This is a legal requirement, and non-compliance is a punishable offense.
To provide equipment (AFS 2001:3, provision on the use of Personal Protective Equipment).