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Comment by dragon_greens | Hacker News Reader

Simply heating does not kill all bacteria magically. That would require boiling for some time and I doubt that happens in-flight.

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Heat absolutely does kill bacteria. Heating water for just a few minutes at 60C will kill e. coli, 70C will kill it instantly. Coffee is brewed at 90-100C.

[1] https://academic.oup.com/jtm/article-pdf/3/1/11/5107757/jtm3...

Airplanes are not pressurized to sea level though, water boils at lower temperatures at altitude.

On airplanes, pressure is equivalent to about 2000m ASL, at which water boils at 93.4 °C

There are several ski resorts at 2000m, you notice the difference in coffee temperature from sea level.

Yeah, but not "magically".

yea wilderness survival says full boil for at least 3 minutes, more in higher altitude. While shopping for an on-demand hot water tap, I couldn't find a single one that even went up to boiling temperature, so my hunch is that airplanes don't even boil for a second.

It depends on what you're trying to kill. Some bacteria perish quickly at less-than-boiling temperatures. In the wild, you have spores and other hardy organisms that require a lot more heat and time to kill.

The 3 minutes idea is to kill anything that may be deeply imbedded the bits of wood, leaves, and other detritus suspended in the water.

It's generally considered paranoid overkill when you consider the water will take a while to cool - it will stay in the "kill everything" temperature for quite a while in the process.

https://besurvival.com/guides/how-long-should-you-boil-water

Also, 'boiling' at the cabin pressure is not quite normal boiling.

The safe temperature for killing bacteria is about 140°F or 60°C. To get water to boil at that low a temperature requires about ⅕ atmospheric pressure, or roughly the atmospheric pressure outside the aircraft.

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