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A cable, fuse box, or junction box that feels warm may indicate too much current in the circuits.

A burning odor may indicate overheated insulation.

Worn, frayed, or damaged insulation around any wire or other conductor is an electrical hazard because the conductors could be exposed. Contact with an exposed wire could cause a shock. Damaged insulation could cause a short, leading to arcing or a fire. Inspect all insulation for scrapes and breaks. You need to evaluate the seriousness of any damage you find and decide how to deal with the hazard.

A GFCI that trips indicates there is current leakage from the circuit. First, you must decide the probable cause of the leakage by recognizing any contributing hazards. Then, you must decide what action needs to be taken.

Any of these conditions, or clues,” tells you something important: there is a risk of fire and electrical shock. The equip- ment or tools involved must be taken out of service. You will fre- quently be caught in situations where you need to decide if these clues are present. A maintenance electrician, superviso , or instruc- tor needs to be called if there are signs of overload and you are not sure of the degree of risk. Ask for help whenever you are not sure what to do. By asking for help, you will protect yourself and others.

Summary of Section 6 Look for “clues” that hazards are present.

Evaluate the seriousness of hazards. Decide if you need to take action. Don’t ignore signs of trouble.

A n 1 8 - y e a r - o l d m a l e w o r k e , w i t h 1 5 m o n t h s o f e x p e r i e n c e a t a f a s t f o o d r e s t a u r a n t , w a s p l u g g i n g a t o a s t - e r i n t o a f l o o r o u t l e t w h e n h e r e c e i v e d a s h o c k . S i n c e t h e r e s t a u r a n t w a s c l o s e d f o r t h e n i g h t , t h e f l o o r h a d b e e n m o p p e d a b o u t 1 0 m i n u t e s b e f o r e t h e i n c i d e n t . T h e r e s t a u r a n t m a n a g e r a n d a n o t h e r e m p l o y e e heard the victim scream and investigated. The victim was found with one hand on the plug and the other hand grasping the metal receptacle box. His face was pressed against the top of the outlet. An employee tried to take the victim s pulse but was shocked. The manager could not locate the correct breaker for the circuit. He then called the emergency squad, returned to the breaker box, and found the correct breaker. By the time the circuit was opened (turned off), the victim had been exposed to the current for 3 to 8 minutes. The employee checked the victim s pulse again and found that it was very rapid.

The manager and the employee left the victim to unlock the front door and place another call for help. Another employee arrived at the restaurant and found that the victim no longer had a pulse. The employee began administering CPR, which was continued by the rescue squad for 90 minutes. The victim was dead on arrival at a local hospital.

Late , two electricians evaluated the circuit and found no serious problems. An investigation showed that the victim s hand slipped forward when he was plugging in the toaster. His index finger made contact with an energized prong in the plug. His other hand was on the metal receptacle box, which was grounded. Current entered his body through his index finge , flowed across his chest, and exited through the other hand, which was in contact with the grounded receptacle.

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    prevent death or injur , you must recognize hazards and take the right action.

    • If the circuit had been equipped with a GFCI, the current would have been shut off before injury occurred.

    • The recent mopping increased the risk of electrocution. Never work in wet or damp areas!

    • Know the location of circuit breakers for your work area.

Section 6

Page 37

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