Victorinox Explorer Plus

by Greg Lyons
(Allston, Ma.)

Victorinox Explorer Plus & Leatherman PST

I carry a Victorinox Explorer Plus in my back pocket next to my wallet and a 20+ year old Leatherman PST1 on my belt. EVERYDAY/ALL DAY. The only time that I don't have them on my person is when I'm sleeping or prohibited by law.

The reason that I'm writing to you is that you made a serious mistake on your page about water purification. Your quote: "If you are at a higher elevation, boil the water for several minutes, the boiling point for water is higher at elevations."

The boiling point of water is 212 degrees F (100 degrees C) at sea level (standard conditions, 1 Atmosphere/760 mmHg). As your altitude increases, the atmospheric pressure decreases (usually). As the pressure decreases the vapor pressure of the fluid increases. As the vapor pressure of the fluid increases it takes less heat, and therefore a lower temperature, to boil. A somewhat rough rule of thumb for water is for every 1000' in elevation gained, the boiling point of water decreases about 1 degree C.