What is Electric Arc Flash?
Electric arc flash is one of the most serious and least understood electrical hazards. An electric arc is a continuous electric discharge of high current between conductors, generating very bright light and intensive heat. An arc flash occurs if this discharge is caused by a short circuit because of technical failure of electrical equipment or, in the majority of cases, by mistakes of the workers.
What are the consequences of electric arc flash?
Depending on the severity of the arc flash, it can lead to:
- Blast pressure (up to 1000 kg / m2)
- Sound blast (up to 140dB – as loud as a gun)
- Heat (up to 20,000 °C)
The consequences for people working on or close to energized electric equipment will depend on the amount of Incident Energy received at the body surface, which depends on its distance from the arc. The primary concern for the exposed person is skin burns.
When does electric arc flash occur?
Electric arc flash can occur whenever and wherever electrical equipment is live. During maintenance or repair, if for any reason the equipment cannot be made “dead”, then an electric arc can occur.