Candles are useful when oxygen has been consumed because of respiration or a fire. They're not useful in a leak.

Conservation of mass: if a cubic meter of air escapes, that's 1.25 kg, and you need at least that much in candles. (You actually need 2 kg because the candle isn't solid oxygen)

There's ultimately 1.2 t of atmosphere on the ISS. This will also result in a pure oxygen atmosphere, which is dangerous. You need nitrogen.

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pyuser583 an hour ago | parent [-]

I thought it had a pure oxygen atmosphere to prevent the bends? Why is it dangerous?

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avmich 35 minutes ago | parent [-]

Apollo I disaster suggests pure oxygen atmospheres are to be avoided.

	▲	sam1714 4 minutes ago \| parent [-]
		And the 1961 fire that killed cosmonaut Valentin Bondarenko in an altitude chamber. The Soviets covered it up until the 1980's, so NASA made the same mistake.