US Dept of Labor

Occupational Safety & Health AdministrationWe Can Help

OSHA Occupational Safety and Health Administration
U.S. Department of Labor

Process: Shipboard Electrical

 

Electrical hazards that may result in arc flash

Case History #1

An electrician was working on a circuit breaker panel that he thought was deenergized. After completing the work, the electrician was closing one of the enclosure doors when an arc flash occurred. Electric current from the energized panel moved through the air to the closed panel door. The rapid release of energy caused the panel door to fly open, hitting the worker and knocking him unconscious as the panel continued to arc.

Analysis & Preventive Measures

Although the electrician believed that all power had been deenergized from the electrical panel, this incident could have been prevented by voltage testing the electrical panel before starting work. Taking the time to perform a simple test can ensure workers’ safety.

Often arc flashes occur when reenergizing panels after maintenance. Proper cleaning is one method of reducing this hazard.

Case History #2

An electrician and a coworker were retrofitting dated equipment, installing new buckets on a switch gear. The electrician mechanically disconnected the switch, but he did not test it to verify deenergization. As he attempted to remove the switch from the switch gear, an arc flash occurred. The electrician was severely burned and suffered acute respiratory stress.

Analysis & Preventive Measures

Disconnecting the switch was not sufficient to prevent the flow of electricity through the equipment. The equipment should have been voltage tested to verify that it was deenergized before beginning work, as all sources of power to the equipment were not secured.

D21

Back to Top

Thank You for Visiting Our Website

You are exiting the Department of Labor’s Web server.

The Department of Labor does not endorse, takes no responsibility for, and exercises no control over the linked organization or its views, or contents, nor does it vouch for the accuracy or accessibility of the information contained on the destination server. The Department of Labor also cannot authorize the use of copyrighted materials contained in linked Web sites. Users must request such authorization from the sponsor of the linked Web site. Thank you for visiting our site. Please click the button below to continue.

Close