May 19, 1999

On May 19, 1999, at 10:31 a.m., four Western Area Power Administration (Western) employees were performing Doble testing on a circuit breaker at Hayden Substation in Routt County, Colorado. Three electricians were injured when the high-voltage lead (HVL) of the Doble test set encroached on the minimum approach distance to an energized part outside clearance boundaries, drawing arcing faults.