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I'm 99% sure that any boiling will kill nearly all germs in water. I don't have facts on hand, but I do remember that once you get above ~160F, nearly all germs

I'm 99% sure that any boiling will kill nearly all germs in water. I don't have facts on hand, but I do remember that once you get above ~160F, nearly all germs are dead. So boiling water will definitely kill everything.

chc 9y ago
According to the CDC, at elevations above 6,500 feet, water needs to be boiled for three minutes to kill E. coli.
- Bartweiss 9y ago
  That's a pressure issue, though - low air pressure drops boiling temperature, so your water doesn't actually get as hot. Most commercial aircraft are pressurized to around 11psi, which is an elevation of ~3,500 feet.
falsedan 9y ago
It will kill the pathogens which cause vomiting and diarrhea: the article mentions e. coli, which the CDC[0] recommend 1 minute at boiling temperature to deactivate. I'd skip that and stop as soon as the water boiled. Note that sterilization requires higher temperatures for longer periods, but it's not required for food products consumed by the general public. Some bacteria may survive the boiling process, but your stomach acid + immune system will destroy them. [0]: https://www.cdc.gov/healthywater/drinking/private/wells/disease/e_coli.html https://www.cdc.gov/healthywater/drinking/private/wells/dise...
- rdoherty 9y ago
  Good point! That's why posting on HN is so great, even if you're 99.9% correct, someone will always reply to tell you precisely how you are 0.1% wrong . Thanks for the link, I tried to find official sources online and had trouble.
  - falsedan 9y ago
    To be clear, I think your original comment is just fabulous and you're 100% right. I'm just curious since I know that controlling the level of E. coli contamination in milk is important from first-hand work on dairy farms, plus I know that pasteurization heats (not boils) the milk, and not for the ridiculous durations I see when searching online for "making water safe to drink".
    - mattkrause 9y ago
      Also, the relevant factor is not just temperature--it's a combination of time and temperature. For milk, you can do 1-2 seconds at 135C (UHT), 15 sec at 72C (HTST), or something like 20 min at 60C.
Symbiote 9y ago
Boiling point reduces as pressure reduces. Cruising altitude on a plane is roughly equivalent to air pressure at 1800-2400m, so using [1] that means water boils at around 93°C. (If I had any familiarity with Fahrenheit, I wouldn't have bothered looking this up. 160°F = 70°C, and even on Everest water boils at a higher temperature.) [1] http://docs.engineeringtoolbox.com/documents/1344/boiling_point_water_elevation_meter.png http://docs.engineeringtoolbox.com/documents/1344/boiling_po...
Jedd 9y ago
> I'm 99% sure that any boiling will kill nearly all germs in water. I don't have facts on hand, but I do remember that once you get above ~160F, nearly all germs are dead. So boiling water will definitely kill everything. Occasionally I find out that something that I thought / hoped / believed to be the case ... wasn't. Killing 'nearly all germs' is good, but not really what you need when you may get sick or die from the kinds of germs that don't fit the 'nearly all' category. Cryptosporidium and giardia (two things that Sydney residents became overly familiar with before our Olympic hosting) require a few minutes of rolling boil to kill. And the definition of 'rolling boil' becomes more onerous as you increase your altitude.
dragonwriter 9y ago
> I'm 99% sure that any boiling will kill nearly all germs in water. CDC says a full minute of boiling (3 minutes for elevations greater than 6,500ft) to deal with (the problem strain of) E. coli in well water. Momentary boiling is not sufficient for safety. https://www.cdc.gov/healthywater/drinking/private/wells/disease/e_coli.html https://www.cdc.gov/healthywater/drinking/private/wells/dise...

chc 9y ago

According to the CDC, at elevations above 6,500 feet, water needs to be boiled for three minutes to kill E. coli.

Bartweiss 9y ago
That's a pressure issue, though - low air pressure drops boiling temperature, so your water doesn't actually get as hot. Most commercial aircraft are pressurized to around 11psi, which is an elevation of ~3,500 feet.

falsedan 9y ago

It will kill the pathogens which cause vomiting and diarrhea: the article mentions e. coli, which the CDC[0] recommend 1 minute at boiling temperature to deactivate. I'd skip that and stop as soon as the water boiled. Note that sterilization requires higher temperatures for longer periods, but it's not required for food products consumed by the general public. Some bacteria may survive the boiling process, but your stomach acid + immune system will destroy them. [0]: https://www.cdc.gov/healthywater/drinking/private/wells/disease/e_coli.html https://www.cdc.gov/healthywater/drinking/private/wells/dise...

rdoherty 9y ago
Good point! That's why posting on HN is so great, even if you're 99.9% correct, someone will always reply to tell you precisely how you are 0.1% wrong . Thanks for the link, I tried to find official sources online and had trouble.
- falsedan 9y ago
  To be clear, I think your original comment is just fabulous and you're 100% right. I'm just curious since I know that controlling the level of E. coli contamination in milk is important from first-hand work on dairy farms, plus I know that pasteurization heats (not boils) the milk, and not for the ridiculous durations I see when searching online for "making water safe to drink".
  - mattkrause 9y ago
    Also, the relevant factor is not just temperature--it's a combination of time and temperature. For milk, you can do 1-2 seconds at 135C (UHT), 15 sec at 72C (HTST), or something like 20 min at 60C.

Symbiote 9y ago

Boiling point reduces as pressure reduces. Cruising altitude on a plane is roughly equivalent to air pressure at 1800-2400m, so using [1] that means water boils at around 93°C. (If I had any familiarity with Fahrenheit, I wouldn't have bothered looking this up. 160°F = 70°C, and even on Everest water boils at a higher temperature.) [1] http://docs.engineeringtoolbox.com/documents/1344/boiling_point_water_elevation_meter.png http://docs.engineeringtoolbox.com/documents/1344/boiling_po...

Jedd 9y ago

> I'm 99% sure that any boiling will kill nearly all germs in water. I don't have facts on hand, but I do remember that once you get above ~160F, nearly all germs are dead. So boiling water will definitely kill everything. Occasionally I find out that something that I thought / hoped / believed to be the case ... wasn't. Killing 'nearly all germs' is good, but not really what you need when you may get sick or die from the kinds of germs that don't fit the 'nearly all' category. Cryptosporidium and giardia (two things that Sydney residents became overly familiar with before our Olympic hosting) require a few minutes of rolling boil to kill. And the definition of 'rolling boil' becomes more onerous as you increase your altitude.

dragonwriter 9y ago

> I'm 99% sure that any boiling will kill nearly all germs in water. CDC says a full minute of boiling (3 minutes for elevations greater than 6,500ft) to deal with (the problem strain of) E. coli in well water. Momentary boiling is not sufficient for safety. https://www.cdc.gov/healthywater/drinking/private/wells/disease/e_coli.html https://www.cdc.gov/healthywater/drinking/private/wells/dise...