Safety and work practicesQuestion 786 of 1506

What is the greatest hydrogen hazard in a room with batteries on charge?

Hydrogen collecting in the room until something ignites it
Hydrogen's heavy weight that pushes it to the floor
Hydrogen's strong smell, which is always noticed first
Hydrogen's toxic colour, which is easy to see in a room

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Correct answer: Hydrogen collecting in the room until something ignites it

Hydrogen is light and rises. It is dangerous when allowed to build up.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 11.5: Practical Considerations - Batteries

Questions last reviewed: 18 October 2026

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