Electrical Safety Hazard Alert Issued

OSHA has issued a hazard alert, warning workers and employers of the dangers of using certain Eaton/Cutler-Hammer molded-case circuit breakers that were incorrectly rebuilt. The third-party rebuilder may have altered the circuit breakers – identified by model numbers E²K and E²KM – by using incorrect parts that can cause the breakers to malfunction.


The breakers were originally manufactured by Eaton/Cutler-Hammer as part of its E² mining series breakers. At this time, the number of incorrectly rebuilt E²K and E²KM breakers or their locations are not known. The circuit breakers may appear to be new or properly rebuilt, but the third party rebuilder changed them from the manufacturer’s original design.


OSHA developed this alert based on a similar notice recently issued by the Mine Safety and Health Administration. The alert warns that the rebuilt circuit breakers have incorrect voltage ratings on the covers. Because the covers do not meet manufacturer’s specifications, they may lack proper safety features such as grounding and fault protection to prevent electrical shock, burns and fires. Since the potential for worker injury from breaker failure exists, employers must remove this equipment from service.


Instructions for what employers should do if their worksites are using E²K and E²KM breakers are listed in the alert. Employers should have a qualified person shut off power to the breakers, follow proper lockout/tagout procedures, and remove any defective breaker from service and replace it with one that a Nationally Recognized Testing Laboratory (NRTL) has properly certified.


Although the E²K and E²KM circuit breakers are intended for use in mining operations, OSHA recognizes that employers performing tunneling operations may purchase the same breakers.