Technician exam question T0A01
Subelement T0, SAFETY· Group T0A
Which of the following is a safety hazard of a 12-volt storage battery that lacks internal protection circuitry?
- A.Touching both terminals with your hands can cause electrical shock
- B.Shorting the terminals can cause burns, fire, or an explosion (correct answer)
- C.RF emissions from a nearby transmitter can cause the electrolyte to emit poison gas
- D.All these choices are correct
WhyShorting the terminals of a 12-volt storage battery that lacks internal protection circuitry can cause burns, fire, or an explosion. A 12-volt battery can deliver enormous current into a dead short, and that current can generate enough heat to cause burns, ignite nearby materials, or even rupture the case violently, answer B. Twelve volts alone isn't normally enough to shock a person through intact skin just by touching both terminals (A), and a nearby transmitter's RF energy isn't what causes a battery's electrolyte to emit gas, that's a byproduct of charging or a short circuit instead (C), so D, which depends on all three being real hazards, is also wrong.
Published 2026-08-28 · Last updated 2026-08-28 · Question text is verbatim from the 2026-2030 NCVEC Element 2 pool (public domain); the explanation above is original writing, see our methodology.
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