Life gear glow stick
REI link

{ 1.3 oz, 7.5 inches}

runs 200 hours, 4 modes, includes ( for some reason) a whistle and is $5 at Target. Will this replace chemical lights?

200 hours @ $5 is cheaper than 10 chem light sticks ( even at .50 each and 12 hours run time= is 120 hours of light.)

check some of the offerings.
http://www.essentialgear.com/store/default.aspx

It includes a whistle because it's trying to be many things to many people.

I checked this out at REI just the other day. None of the light modes is very bright but I suppose that is a fair trade off for more modes of operation vs. chem. light sticks.

AG13 batteries are sure to be harder to find but are small enough to store away many spares without using much space.

Overall, I'd consider it an acceptable backup to a backup, but certainly not an acceptable primary light for a preparedness kit.

For the price, they make great giftsfor kids past the "choking hazard" stage.

Will it replace chemical lights?

Tell you what. Let's put you in a darkened room full of an explosive gas-oxygen mix and have you pull out a light and read a newspaper. You can either pull out a chemical light or a Life Gear Glow Stick. Knowing that any spark will mean a violent and painful death should make your choice for you.

You might also consider what you want to carry if your using the light on the ocean and will need it after it has been in saltwater spray for a few months.

Chemical lights are not perfect. They have weaknesses. They deteriorate in performance as they age, particularly if the foil wrapper is breached. The light is not all that bright, they only run for about 12 hours and once activated they can't be turned off to extend their useful life, and once expended they are useless.

On the other hand they are safe around explosive atmospheres. They are immune to most corrosive agents and solvents. They are non-toxic, cheap, reliable as long as they are rotated, and they are both light and compact.

If I were going to go for a replacement for chemical lights, I'd recommend this one:

http://www.lighthound.com/Glo-Toob-Lithium-Green_p_570.html

Glo-Toob lithium is rated for scuba diving, and uses CR123 batteries, so it lasts 24-100 hours (depending on what cycle you use). Several different colors, and it has a good reputation on places like candlepowerforums.com.

Of course, it's a lot more expensive, but nearly unbreakable, and has the advantages that CR123s offer (availability, battery life).

That link is, in my experience, a very good source for flashlights and related items - no business interest, etc.

Dave

Hmmm...I think the last thing on my mind if I were in a room "full of an explosive gas-oxygen mix" would be reading the newspaper...;^)

If the O2 content is less than 16% in that room I'd already be dead anyway no matter what kind of light I had in my pocket.

I live in an area prone to earthquakes, and the issue for us is whether there's a gas leak after a quake. We keep glowsticks on hand so we can have light while we escape without blowing the place up when we get to where ever the leak is.

We keep both electric lights and chem lights because each serves a different purpose.

Why 16%? Normal is about 20% and at 10KFT the partial pressure should be less than 16% at sea-level, I think, maybe, haven't done the math. What about <16% O2 is the killer?

Yeah, I think someone is getting numers mixed up.

Normal air is 21% oxygen - at any altitude. The problem is the partial pressure drops with altitude, so there's less barometric pressure... blah blah blah. I'd be BS'ing if I said anything else, but I know that's the big problem with elevation and altitude sickness. I'd hazard a GUESS that the partial pressure of O2 in the blood needs a pressure gradient, and the drop from altitude makes it harder to transfer.

16% is the amount of oxygen in the breath exhaled.

FWIW, I have absolutely NO idea how "little" oxygen is needed to keep alive. I know that you can get up to 100% inhaled oxygen, but not the other way. Anyone?

Sorry, I added a 1 where I shouldn't have, meant to write "6%". Other points remain, if a person is in a room full of explosive gas the last thing that they'll be doing is attempting to read a newspaper.

21% is the amount of O2 in "normal" air. Any drop below that leads to to symptoms of O2 deprivation, dizziness, nausea, etc. A drop to 12% or less leads to unconsciousness, further drop ie, to 6% or less leads to rapid death.