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Science: Health: Eye: Glasses
Anti-Fog specs   (+9)  [vote for, against]
Dealing with humidity

A tree came down in my yard after a short but heavy storm. It came down right on top of my electric scooter (no damage!), and also covered the sidewalk.

It was still very wet out, the rain was not quite over yet, and the day had been warm. The chainsaw purred at a quiet idle as I moved around the tree, removing limbs and cutting stove lengths from the trunk to clear the sidewalk.

After a few short minutes I had to remove my glasses, as the combination of work, heat and humidity had fogged them to an opacity usually reserved for frozen beer mugs. No amount of wiping would keep them clear. I couldn't put my contacts in because I don't have contacts, and wouldn't wear them while operating a chainsaw in any case.

I took my glasses off, and set them in a safe place while I continued to work with the chainsaw. My eyesight is bad enough that this is possibly the dumbest thing I have done all year. Be that as it may, operating the chainsaw while still wearing the glasses in their current state would have been dumber still.

My proposal is this: a loop of nichrome heating element wire incorporated into the frames of my glasses could provide enough heat to prevent - or at least reduce - condensation on the lenses. It doesn't take a lot of heat to do this, same as it doesn't take a lot of air movement to prevent condensation. The ideal combination would be to provide a warm airflow, but that requires additional gear; this requires only the glasses - which I already wear, and the heating elements would add virtually no weight - and a cord and battery that could be kept in a pocket or on my belt, and attached only when needed. I already spend much of my day with a personal stereo, Leatherman and flashlight on my belt, so I know the cord and weight are not onerous.
-- elhigh, Jul 20 2005

The Pink Stuff
for ElDorado [junglefish, Jul 20 2005]

Anti-fog safety glasses http://www.safetygl...m/foc1silframc.html
[junglefish, Jul 20 2005]

couldn't you generate enough power by waggling your ears? +1 for a fellow fallen-tree-in-back-garden victim.
-- po, Jul 20 2005

Going in and out of refrigerated office buildings in the latter part of a New York summer, I sometimes have to remove my glasses in seconds, not minutes - they fog up instantly.
-- DrCurry, Jul 20 2005

Paintball players have a similar problem with goggles, especially during a hot, sweaty day of running around the woods. The solution? Double-lens goggles. The outer lens stays the outside temp, the inner the temp of your face, and they don't fog. At least, not that much. You can get a little fan that exhausts the sweaty air, too.

The goggles are pretty bulky, though. Probably not attractive for people who like their glasses sleek and svelte.

Here's a [link] for EDJ. I used to use this stuff, too, with some success. Now I just wear contacts and, when necessary, safety glasses, which come with an anti-fog option. [another link]
-- junglefish, Jul 20 2005

I got tackled at the Valley Fair one year by some shmoe trying to sell the pink stuff - though his was green - and lo and behold, it worked! Rather, it worked until I sweated it right off, and then my glasses began to fog in streaks. My glasses are quite close to my face, actually brushing my brows. Turns out the antifog goo is just a gelled detergent with a little glycerin.

I considered a fan, but I wonder if that would help, it might just fog up faster. A thin breeze of warm air would work best, but Lordy it's hot enough already.

I also considered a Peltier device, to warm the air the fan would blow, and the cold side would be ducted to blow cool air under my hat to help counter the added heat on my glasses. At this point, we're talking about a very bulky device on my head that is powered by a battery pack at least equal in weight to the stereo, flashlight, and Leatherman combined. In defence of that, I've worn a powered air supply helmet with face shield for woodturning, and it was bulky as hell, but add on the earmuffs for the chainsaw and it's no less bulky than what is minimum recommended chainsawing gear.

With all the ducting and the face shield and helmet, I'd look like a chainsaw-wielding Darth Vader.
-- elhigh, Jul 21 2005

Looking like a chainsaw-wielding Darth Vader has certain advantages. +
-- ato_de, Feb 06 2006

Spit and polish. Like piss and vinegar, but more useful.
-- 4whom, Nov 13 2007

random, halfbakery