Originally Posted By ohiohiker


Another time filters won't work is when it's below 32F. They'll freeze, develop small cracks you can't see, and that will allow the bad stuff to pass through.


The filter will work at any temperature. You cannot leave it out in the cold long enough to freeze, is all. If you are hiking in freezing temps chances are good you won't be filtering anyway - you'll be melting snow. If it is just subfreezing at night put the filter in the footbox of the sleeping bag.


Edited by lori (08/22/12 05:15 PM)
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