Static electricity during vacuum operations can result in accidents such as shock hazards, explosions, and secondary injuries from falls due to shock, the Mine Safety and Health Administration has warned in a safety alert for vacuum trucks.
The agency recommended best practices to assist miners in staying safe during vacuum operations, including:
- Make certain that the truck is connected to an object that is grounded;
- Make certain the truck has a connection that is monitored continuously for the duration of the operation;
- Use interlocks to trigger the shutdown of the transfer operation when a break in the connection to earth occurs; and
- Use conductive or semi-conductive hoses and regularly test their continuity.
MSHA urged miners to exercise extreme caution in and around vacuum trucks because of potentially life-threatening hazards. The agency issued the safety alert to other industries that use vacuum trucks, such as telecommunication and water/sewer utilities.