Case Study
At about 1:45 a.m., two journeyman electricians began replacing bulbs and making repairs on light fixtures in a spray paint booth at an automobile assembly plant.
The job required the two electricians to climb on top of the booth and work from above. The top of the booth was filled with pipes and ducts that restricted visibility and movement. Flashlights were required.
The electricians started at opposite ends of the booth. One electrician saw a flash of light, but continued to work for about 5 minutes, then climbed down for some wire.
While cutting the wire, he smelled a burning odor and called to the other electrician. When no one answered, he climbed back on top of the booth. He found his co-worker in contact with a single-strand wire from one of the lights. Needle-nose wire strippers were stuck in the left side of the victim's chest. Apparently, he had been stripping insulation from an improperly grounded 530-volt, single-strand wire when he contacted it with the stripper. In this case, the electricians knew they were working on energized circuits. The breakers in the booth's control panel were not labeled and the lock used for lock-out/tag-out was broken. The surviving electrician stated that locating the means to de-energize a circuit often takes more time than the actual job.
The electrician would be alive today if the following rules had been observed.
- Always shut off circuits - then test to confirm that they are de-energized - before starting a job.
- Switchgear that shuts off a circuit must be clearly labeled and easy to access.
- Lock-out/tag-out materials must always be provided, and lock-out/tag-out procedures must always be followed.
- Always label circuit breakers.
Knowledge Check Choose the best answer for the question.
7-2. After shutting off circuits, what should you do prior to starting work on the circuits?
You forgot to answer the question!