Exposed Electrical Parts Hazards
Being "exposed" to electrical parts occurs when a person can inadvertently make contact with an energized conductor or circuit part.
An "electrical part" is considered exposed if it is not properly guarded, isolated, or insulated. So if you can touch a bare part, then it’s considered exposed. Some common exposed parts to look for include:
- wires, if a cover is removed from a wiring or breaker box;
- overhead wires coming into a home may be exposed;
- electrical terminals in motors, appliances, and electronic equipment; and
- older equipment, or equipment that is being serviced.
If the status of an electrical part (live or dead) is not obvious, you can take a closer look using the finger test. If your finger could make it past a guard or through an enclosure opening and touch a circuit part, then the part is considered exposed. In these cases, the guard or enclosure should be re-engineered to properly eliminate the hazard exposure.
If you are possibly exposed to live electrical parts in any of the situations above, before you work on the equipment, first turn off the power, if possible, or otherwise use lockout/tagout procedures or other hazard control measures to prevent or reduce exposure.
Real-life Scenario
Five workers were constructing a chain-link fence in front of a house, directly below a 7,200-volt energized power line. As they prepared to install 21-foot sections of metal top rail on the fence, one of the workers picked up a section of rail and held it up vertically. The rail contacted the 7,200-volt line, and the worker was electrocuted. Following inspection, OSHA determined that the employee who was killed never received any safety training from his employer and no specific instruction on how to avoid the hazards associated with overhead power lines. In this case, the company failed to obey these regulations:
- Employers must train their workers to recognize and avoid unsafe conditions on the job.
- Employers must not allow their workers to work near any part of an electrical circuit UNLESS the circuit is de-energized (shut off) and grounded, guarded in such a way that it cannot be contacted.
- Ground-fault protection must be provided at construction sites to guard against electrical shock.
Knowledge Check Choose the best answer for the question.
2-2. What precautions should you take when working around old motors, appliances, and electrical equipment to eliminate or reduce exposure to live electrical parts?
You forgot to answer the question!