Water Purification by boiling

[billycan]

I was just wondering if anyone had a definitive answer to the time period required for sterilising water by boiling. I have heard various answers, ranging from a few seconds to 15 minutes, even RM has said different things in his programmes.

I usually just bring it to a rolling boil for 20-30 seconds. I have heard that most parasites and bacteria are killed at about 80 degrees C and if the water is too hot to put your hand in then its usually ok - seems a bit of an unecessary risk.

Does anyone have an answer or some experiences or thoughts they'd like to share, i'd be interested to hear...

Cheers in advance

 

[spamel]

Just bring it to the rolling boil, I've never had trouble with water treated this way. Some people say you should continue to boil for X minutes, I can't see how bacteria will survive 100 deg C but give up the ghost around 4 minutes and 58 seconds!!!

Also, your body will build up an immunity to nasties given a chance, so even if a few do survive, you'll only make yourself stronger!!

 

[sharp88]

Yeah I heard 5 minites. Id do it for about 10 though - just incase. Immunity is bound to not occur without a bit of the sqwitz.

 

[copper_head]

Guess its finding a balance between evaporation and safety, I always go for 2 minutes(ish) at a rolling boil, never had any trouble.

 

[Cap'n Badger]

''Immunity is bound to not occur without a bit of the sqwitz''
....nice.....true........but 'NICE'..lol.

 

[Tadpole]

I usually just bring it to a rolling boil for 20-30 seconds. I have heard that most parasites and bacteria are killed at about 80 degrees C and if the water is too hot to put your hand in then its usually ok - seems a bit of an unecessary risk.

most are, some aren't some like Blue green algae (cyanobacteria) They are not an true algae but a photosynthetic bacteria, they live in shallow water and boiling the water (if they are present) does nothing to them, some scientists say it helps to release more of the harmful toxins. blue-green algae have been found to be growing in the hot springs of Yellowstone National Park's steaming geysers, enduring and thriving in water temperatures as high as 160°C.

 

[Glen]

I was just wondering if anyone had a definitive answer to the time period required for sterilising water by boiling. I have heard various answers, ranging from a few seconds to 15 minutes, even RM has said different things in his programmes.

I usually just bring it to a rolling boil for 20-30 seconds. I have heard that most parasites and bacteria are killed at about 80 degrees C and if the water is too hot to put your hand in then its usually ok - seems a bit of an unecessary risk.

The definitive answer will involve at what altitude your boiling it, water boils at a lower temperature the higher you go. I suspect out climbing friends will have a formular, but most are rules of thumb and hence expect them to vary at least a little.

 

[BOD]

We are all too anal about water purification. It is the aesthetics that put us off. We were designed by God to drink less than "pure" water

We are more likely to get some poisoning or bug through old pipes at home and sloppy restaurant kitchen hygiene than a deadly germ from a clear stream away from human habitation. A dead animal upstream is not much of a threat but a human campsite is.

Unless it is really bad looking and smelling it is unlikely to do that much to us.

Get it to a boil and then take it off the fire and make a cup of tea to improve the taste

 

[rik_uk3]

At sea level, most nasty stuff in the UK at least will die at 80c, boil for a few minutes won't harm though. I think its down to temperature, not the rolling boil which varies with altitude?

 

[locum76]

Get it to a boil and then take it off the fire and make a cup of tea to improve the taste

indeed, you don't have to have a rolling boil at all just get it hot enough to make a nice cup of tea. for anyone who's worried about water purification - all of the best solutions are here...

http://www.wemjournal.org/wmsonline...an=ALL&lname=&hits_per_page=10&sort=relevance