I quote my information as provided by the US EPA, and a host of other online official sources. One minute at hard boil seemed to be the SOP recommendation.

If you can get the water to a boil, keeping it there for a minuts shouldn't be much more of a challenge.
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The ultimate result of shielding men from the effects of folly is to fill the world with fools.
-- Herbert Spencer, English Philosopher (1820-1903)