Definition - What does Arc Blast mean?
An arc blast is the name given to the explosive burst of energy that occurs during an arc flash. An arc blast occurs as the result of a malfunction in the insulation between two energized phase conductors on high powered electrical equipment. Rather than flowing through a conductor, the current flows through the air, which releases thermal energy into the immediate environment.
Safeopedia explains Arc Blast
Arc blasts are responsible for in excess of 2000 work related burn injuries in the United Sates each year. That equates to between five and ten arc flash incidents every single work day. In an effort to bring down the incidence of arc flash and resultant arc blasts, the NFPA70E standard was introduced. It is recognized by OSHA as an industry wide written standard which is to be complied with by employers.