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n2ize
07-18-2015, 06:27 PM
I am forever misplacing my kleys or having trouble locating them in the dark so I recently ordered one of those inexpensive Tritium key chain lights. I received it today. It glows a yellow/green colour. I chose green because it's the most visible colour. It's not very bright but it's fine under dark or semi dark conditions. Not quite as bright as the old radium lights but still good enough for practical use. It's basically a laser sealed phosphor coated glass tube containing a minuscule amount of radioactive tritium hermetically sealed in a clear polycarbonate enclosure. Tritium has a half life of 12.6 years so, in 10-12 years it will probably be only about half as bright as it is now. I held it up to a Geiger counter and there was hardly any increase in counts per minute. Contrast that with one of my old radium dial pocket watches that make the Geiger counter click away like crazy if I bring it close to the tube. Radium has a half-life of >1000 years so watches painted with radium are still quite as radioactive as when they were made decades ago. The only reason they no longer glow is because over 10-12 years the phosphor goes bad. Although they don't last as long the tritium lights are considerably safer.

VE7DCW
07-18-2015, 07:09 PM
Wasn't tritium(an isotope of hydrogen)used to ''salt" thermo-nuclear warheads to increase the ultimate yield of the weapon?

I'm not a nuclear physicist,but I seem to remember reading somewhere that was what this material was used for.....if this flashlight was shielded enough to prevent radioactive exposure from beta decay then it seem an appropriate use for this dangerous material! :-|

n2ize
07-18-2015, 08:30 PM
Wasn't tritium(an isotope of hydrogen)used to ''salt" thermo-nuclear warheads to increase the ultimate yield of the weapon?


Yes, it was called a "booster" or "boosting agent" to improve/enhance the efficiency of the fission within fission type atomic bombs. Ultimately this might also enhance yields and help to prevent a fizzle.



I'm not a nuclear physicist,but I seem to remember reading somewhere that was what this material was used for.....if this flashlight was shielded enough to prevent radioactive exposure from beta decay then it seem an appropriate use for this dangerous material! :-|

I think tritium is a byproduct of nuclear reactors. This rather expensive gas is collected and sold for various purpose. One common purpose is radioluminescence. I thin Navy Seal watches were among the first to use it for illuminating watch dials. Of course it's now available for a wide range of illumination from gun sights to instruments to keychains. I don;t think beta exposure is much of an issue since it barely read on my Geiger counter. But if I put the face of a 50+ year old radium watch next to my counter it clicks like mad. The problem with old radium painted dials is that they last for well over 1000 years but the radium also decays into radon, polonium. Radium generally emits alpha particles but its daughter isotopes start giving off beta and gamma rays as the radium decays. Also as they age the binder in the paint starts to wear out and thus the radioactive paint can crumble and flake off as a fine dust. This can be risky if you need to open and fix and old radium dial watch. You have to be careful not to inhale or swallow any minute dust particles. A disposable mask and gloves are recommended. I have a couple old radium pocket watches I wear occasionally. But I am hesitant to remove the crystal or open them to work on. If they break down they stay that way. Tritium is much safer in that the tritium is sealed in tiny glass vials. If you accidentally break one all you need do is leave the area for a little while to allow the minuscule amount of gas to dissipate.

NA4BH
07-18-2015, 09:01 PM
Keep the keychain down near the "OL, Knewt Rockne's".

KG4NEL
07-18-2015, 09:16 PM
I've thought about one of those watches, but a useful lifespan of 10 years for a watch that runs $5-800 isn't such a great deal...

n2ize
07-18-2015, 10:24 PM
I've thought about one of those watches, but a useful lifespan of 10 years for a watch that runs $5-800 isn't such a great deal...

I am not entirely sure but, I think some watch companies will replace the tritium tubes on the watch when they go dim. I read on a watch forum that supposedly the "Ball Watch Co." will offer tritium replacement as an option during scheduled maintenance. As with most expensive mechanical watches they require periodic maintenance. Other watch companies may not do this. I would advise anyone buying an expensive tritium watch to see if the manufacturer will replace the tritium when the time comes before buying the watch. Or, just buy an inexpensive LCD watch with an indiglo( R) background light.

KG4NEL
07-18-2015, 10:43 PM
A Ball's too rich for me :oops:

n2ize
07-19-2015, 04:50 AM
A Ball's too rich for me :oops:

Yeah, I know. They are nice and I wouldn't mind having one but they are too rich for me as well. Besides for general day to day timekeeping my smart phone does quite well...not to mention clocks on my desktop computer and just about everywhere I go. Besides, as far as watches go I am mainly into actual antique pocket watches. In fact I have my eye on a beautiful working key winding fusee type pocket watch from the early 1850's. A bit expensive but I might spring for it eventually.

KG4NEL
07-19-2015, 09:59 AM
I probably wouldn't ever be interested in a watch, but I'll need one for nursing school (because patients look at you weird if you pull out a smartphone to time their pulse, pfft). Considering it'll get shoved in a sink approximately 100x per day, I'm figuring a diver is the way to go.

And I'll probably spend 100x more than I need to for it, because, well, male mind and mechanical things.

KK4AMI
07-19-2015, 11:27 AM
If you wouldn't Luv 'em and Leave 'me then you wouldn't have to look for your keys in the dark. Tritium is used in pistol sights for night fighting to😃.

kb2vxa
07-19-2015, 02:11 PM
Ah ptptpthhh. I have a cheap $20 waterproof no frills LCD watch and if I have to see the time in the dark I just push a button. Tritium, that and deuterium in "heavy water" from a hydro plant in Norway were the core of Nazi efforts to develop an atomic bomb. Oh, I found out about it watching season 1 episode 9 of Hogan's Heroes, Go Light On The Heavy Water. Hey look! Collins, the greatest name in radio showed up in it.

n2ize
07-20-2015, 04:38 PM
If you wouldn't Luv 'em and Leave 'me then you wouldn't have to look for your keys in the dark. Tritium is used in pistol sights for night fighting to.

Yep, I've seen them for sale online on various gun supply and hunting supply websites. Before tritium they used radium.

AK4OT
07-20-2015, 05:01 PM
If you wouldn't Luv 'em and Leave 'me then you wouldn't have to look for your keys in the dark. Tritium is used in pistol sights for night fighting to.

Love my tritium sights!

What's super fun is to take some of these:

http://www.mixglo.com/store/p4/T2b_Vials.html

and break them open and put the tritium on things. My kids always crack up when I make them glowing donuts.

n2ize
07-20-2015, 07:22 PM
Love my tritium sights!

What's super fun is to take some of these:

http://www.mixglo.com/store/p4/T2b_Vials.html

and break them open and put the tritium on things. My kids always crack up when I make them glowing donuts.

I take it you're kidding cause it's not possible. Tritium is a gas (hydrogen isotope). As soon as you break the tube the tritium escapes and the tube stops glowing. Now, with radium paint you could make glowing donuts. However consumption of them may significantly shorten the average lifespan.

WØTKX
07-20-2015, 08:05 PM
https://img0.etsystatic.com/000/2/5582518/il_570xN.174122328.jpg

n2ize
07-21-2015, 02:31 AM
Keep the keychain down near the "OL, Knewt Rockne's".

I checked the tritium key chain fob against my Geiger counter. Held 1 inch from the Geiger tube I got normal background radiation levels. Placed directly on the Geiger tube I got normal background levels. In other words the beta particles emitted by the tritium lack the energy to make it outside of the sealed fob. So I would deem it very safe to carry. Even down there.

n2ize
07-21-2015, 02:32 AM
https://img0.etsystatic.com/000/2/5582518/il_570xN.174122328.jpg

Did you like to read these ? I used to enjoy them in my young years. Matter of fact I would probably still enjoy reading one today.

ka4dpo
07-21-2015, 08:20 AM
I take it you're kidding cause it's not possible. Tritium is a gas (hydrogen isotope). As soon as you break the tube the tritium escapes and the tube stops glowing. Now, with radium paint you could make glowing donuts. However consumption of them may significantly shorten the average lifespan.

Ah but it is possible.

"Tritium is a hydrogen atom that has two neutrons in the nucleus, in addition to its single proton, giving it an atomic weight near three. Although tritium can be a gas, its most common form is in water, because, like non-radioactive hydrogen, radioactive tritium reacts with oxygen to form water. Tritium replaces one of the stable hydrogens in the water molecule, H2O, and is called tritiated water (HTO). Like H2O, tritiated water is colorless and odorless. Tritium has a half-life of 12.3 years and emits a very weak beta particle."

http://www.epa.gov/rpdweb00/radionuclides/tritium.html#properties

n2ize
07-21-2015, 09:56 AM
Ah but it is possible.

"Tritium is a hydrogen atom that has two neutrons in the nucleus, in addition to its single proton, giving it an atomic weight near three. Although tritium can be a gas, its most common form is in water, because, like non-radioactive hydrogen, radioactive tritium reacts with oxygen to form water. Tritium replaces one of the stable hydrogens in the water molecule, H2O, and is called tritiated water (HTO). Like H2O, tritiated water is colorless and odorless. Tritium has a half-life of 12.3 years and emits a very weak beta particle."

http://www.epa.gov/rpdweb00/radionuclides/tritium.html#properties

Yeah true. But it's not going to glow. Unless those donuts are glazed with the right phosphor :).

ka4dpo
07-21-2015, 01:07 PM
Phosphor Schmosphor, just smack it around with a few neutrinos.:-D

WØTKX
07-21-2015, 02:58 PM
Did you like to read these ? I used to enjoy them in my young years. Matter of fact I would probably still enjoy reading one today.

Yes. Like all of them. Tom Swift stories were pretty cool, with some bad science.
I graduated to Heinlein, Clarke, Niven, LeGuin, and Norton.
To name a few.

http://cf.ltkcdn.net/party/images/std/154453-380x316-iStock_000016403133XSmall.jpg