Are There Any Caches Using Tritium Light Sources (GTLS),

[+Vinny & Sue Team]

Gaseous Tritium Light Sources (GTLS), also called Tritium Light Sources, are usually small glass ampoules filled with a bit of tritium gas and lined with a thin layer of phosphor that converts the radiation from the tritium into visible light; the glass ampoule is usually sealed in a small oblong capsule-shaped block of clear polycarbonate plastic for protection and to afford toughness and durability. These little light sources are usually rather small, and provide a source of constant non-stop light for periods ranging from 15 years to 30 years (the ultimate limit to effective light-emitting lifetime is limited by the half-life of tritium gas, which is on the order of 12.4 years). And, of course, no batteries are needed, since the tritium gas itself provides the power for the light. These little light-emitting plastic-encased capsules are widely used in perpetual exit signs, in sporting products and for camping, etcetera., and are often sold in colors such as red, blue, pink and green.

 

 

For many reasons, primarily their small size and the fact that they offer a non-stop source of light that will last from 10 to 30 years, they would seem to be fairly ideal for use as a no-batteries-needed, perpetual light source for a night cache, or for marking the way to a cache hidden in a cave, or in an old mine, or in a storm drain tunnel, or in abandoned underground catacombs or fort tunnels, particularly if the cache hider took care to retrieve the GTLS capsule after the cache lifetime was over, to be sure that the capsule was not accidentally crushed or destroyed, etc.

 

 

In my consulting work on time-space portal technologies around the world, I have had many opportunities to play with these little GTLS sources (they are often used by many inventors and developers in portal chambers, which cannot use conventional electrical lighting such as incandescent lamps, fluorescent lamps or LEDs due to the presence of electrical current flow), and I have always been quite impressed with them. A typical GTLS capsule might weigh all of 4 grams, and will often be about twice the size of a typical vitamin C capsule, and yet will emit a fairly bright light, non-stop, for anywhere from 12 years to 30 years.

 

And so, now that my brief introductory preface to GTLS is done, I am wondering if anyone here has ever encountered (or perhaps created) a night cache or underground cache that uses GTLS ampoules in any way? If so, I would love to hear your tales, for these little things are quite fascinating -- many of them put out quite a bit of light, and can easily be seen on a dark night, or in a dark tunnel, from a long distance, and they are also very sturdy and rugged, for they are almost always encapsulated in an outer sheath of solid polycarbonate plastic.

 

I thank you in advance for any of your tales!

 

 

BTW, as a footnote, I should point out that while these GTLS sources are freely and easily available almost everywhere, including hardware stores, building supply stores and camping/hiking stores, all across Asia and in the European Union and in Russia, it is true that the US (and Canada as well) seems to have taken minor and half-hearted steps to keep these devices off store shelves and out of the reach of casual consumers, likely due to fears about the tiny amount of radioactive tritium gas enclosed in the inner glass vials. However, despite these half-hearted efforts at limiting availability of GTLS to consumers in those countries, the reality is that GTLS devices are still easily available to US and Canadian residents for purchase via a number of industrial and commercial distributors, and also via many websites (often for companies located in Europe or Asia) which sell them; United Nuclear often sells them as well on their website. And, GTLS devices are also often offered on Ebay as well. Many vendors do not call them tritium light sources, and rather, tend to call them "glow rings", "glowrings" or "tritium keychain lights".

Edited October 9, 2008 by Vinny & Sue Team

[+Okiebryan]

Intriguing... I've never heard of this. Of course I find out from Mr. Psycho radioactive Vinnie!

[+J10fly]

I've looked into them previously but they are kind of pricy.

[+Renegade Knight]

I've thought about using radioactivity as a means to zero in on a cache. However until your post I've only seen Tritium used as a source of light for night sights on pistols.

 

What kind of radioactivity does tritium give off? (Meaning is the glass sufficient to stop it?)

[+Vinny & Sue Team]

I've looked into them previously but they are kind of pricy.

Hmmm.. .I can usually find them on Ebay or on Hong Kong, Taiwanese or European marketing websites for about $7 to $15 apiece, plus two or three bucks for shipping via first class mail to the USA. I did notice that when United Nuclear (in the USA, and they do tend to be kinda pricey) has them in stock, they sell them for about $30 apiece! Wow! In contrast, I have often found Euro vendors and Hong Kong vendors selling them online for six US dollars!

[+trainlove]

Tritium emits beta rays to turn into Helium 3. Beta's are high speed electrons.

The glass tube mostly absorbs that, and the plastic shell does also. But by Bremsstrahlung interactions Gamma rays are released.

But with Scintillation detectors I have never been able to register anything from the 6 GTLS's that I have, above the normal background. In 2000 I got one of each of the colors that were available at that time.

Background around Massachusetts is about 25 counts per minute with Geiger detectors, and about 200 counts per minute with scintillation counters, at least the ones I have. To see a mininum detectable activity I'd have to measure for a long time.

 

One of my GTLS's has sprung a leak. Well about 4 years ago its plastic shell split open, and the glass tube was found on my floor intact. I epoxy'ed it back in place and it's been fine until sometine this year when the glass tube itself cracked. I can measure it now. When the tube was outside the plastic I could also measure it.

 

The half life is 12.3 years. A light will be half as bright in 12.3 years. It will still be a quarter bright in 24.6 years. And so on for quite a while. They are fairly bright so I think they will still be quite visible for at least 4 or 5 half lives, not 10-20 years.

[+J10fly]

I've looked into them previously but they are kind of pricy.

Hmmm.. .I can usually find them on Ebay or on Hong Kong, Taiwanese or European marketing websites for about $7 to $15 apiece, plus two or three bucks for shipping via first class mail to the USA. I did notice that when United Nuclear (in the USA, and they do tend to be kinda pricey) has them in stock, they sell them for about $30 apiece! Wow! In contrast, I have often found Euro vendors and Hong Kong vendors selling them online for six US dollars!

 

Interesting, i havent found any on ebay just the usual $30 deals online. I have a ton of the actual tritium paint in different colors which i purchased about a year ago for my gun sights. The stuff is very cool and very bright even in daylight.

[+DavidMac]

Tritium is simply radioactive hydrogen with two nuclei. I've heard of it being combined with oxygen to make tritiated water (T2O). According to Wikipedia, these lights emit beta radiation which is supposedly not powerful enough to penetrate the container or skin. However, I'm not sure I want to walk around carrying one in my pocket.

Edited October 9, 2008 by DavidMac

[+Vinny & Sue Team]

I've thought about using radioactivity as a means to zero in on a cache. However until your post I've only seen Tritium used as a source of light for night sights on pistols....

That could easily be done by placing a chunk, perhaps about twelve ounces in weight, of fairly hot (but harmless) radioactive ore -- such things are readily available via Ebay and mineral dealers for about $30 -- in the container, but the fact remains that unless the cache hunter is using an extraordinarily sensitive radiation detector, aka Geiger counter, they will need to be within two or three feet of the cache container before their instrument starts to exhibit a really noticeable spike above background levels.

 

There is, of course, a well-known cache in Delaware (or perhaps on the MD/DE border) which is a multi, and in the first stage it offers the finder a whole pile of wooden popsicle sticks, each imprinted with the supposed coordinates for stage two. However, each stick bears a different set of waypoint coordinates, and there is only ONE wooden stick which bears the correct waypoint coordinates, and it is the one which is quite radioactive! As I recall, my wife Sue had to borrow one of my radiation monitors from my lab to solve this one!

 

What kind of radioactivity does tritium give off? (Meaning is the glass sufficient to stop it?)

Tritium is a radioactive isotope of hydrogen gas, with a half-life of about 12.41 years, and of the three primary types of ionizing radiation -- alpha, beta and gamma -- the radiation emitted by the radioactive decay of tritium is only a weak (i.e., low energy) form of beta radiation, and this beta radiation is entirely stopped by the innermost glass ampoule or envelope holding the gas, and, in any case, the polycarbonate outer housing or shell would also stop all low-energy beta radiation, even if the inner glass capsule were somehow damaged or destroyed. So, there is no radiation from the tritium which ever reaches anyone handling or using tritium light sources [see footnote 1].

 

Footnote 1: Technically, it is true that when the low-energy beta radiation from tritium gas hits the glass envelope of the ampoule (capsule), a tiny amount of gamma radiation is produced. However, since the beta radiation produced by tritium is very low energy, the gamma radiation produced via Bremsstrahlung-type interactions with the glass will be very weak, and is almost never detectable above ordinary normal background radiation levels present in most parts of the world.

Edited October 9, 2008 by Vinny & Sue Team

[+Okiebryan]

I'm not sure I want to walk around carrying one in my pocket.

 

At least not if you plan on having any (more) children!

[+TakeTheLongWay]

As someone mentioned earlier these little tubes are frequently used for night sights for pistols.

 

I have trijicon night sights on both my carry guns and neither my right hip or left ankle has yet to become deformed in any way.

[+Vinny & Sue Team]

Tritium emits beta rays to turn into Helium 3. Beta's are high speed electrons.

The glass tube mostly absorbs that, and the plastic shell does also. But by Bremsstrahlung interactions Gamma rays are released.

But with Scintillation detectors I have never been able to register anything from the 6 GTLS's that I have, above the normal background. In 2000 I got one of each of the colors that were available at that time.

Background around Massachusetts is about 25 counts per minute with Geiger detectors, and about 200 counts per minute with scintillation counters, at least the ones I have. To see a mininum detectable activity I'd have to measure for a long time.

 

One of my GTLS's has sprung a leak. Well about 4 years ago its plastic shell split open, and the glass tube was found on my floor intact. I epoxy'ed it back in place and it's been fine until sometine this year when the glass tube itself cracked. I can measure it now. When the tube was outside the plastic I could also measure it.

 

The half life is 12.3 years. A light will be half as bright in 12.3 years. It will still be a quarter bright in 24.6 years. And so on for quite a while. They are fairly bright so I think they will still be quite visible for at least 4 or 5 half lives, not 10-20 years.

Yes, actually, the GTLS tubes will usually glow to some extent for at least 50 to 80 years, but the manufacturers and vendors usually state their practical, i.e. useful, lifetime as anywhere from 10 to 25 years, simply because of the fact that the device dims with age.

 

And, yes, same here, I have NEVER been able to detect any radiation levels above the normal noise floor (due to normal background radiation levels) from the secondary induced gamma radiation emission from the beta rays hitting the glass, even when I examine the bare glass tubes with a sensitive radiation monitor.

[+Vinny & Sue Team]

I've looked into them previously but they are kind of pricy.

Hmmm.. .I can usually find them on Ebay or on Hong Kong, Taiwanese or European marketing websites for about $7 to $15 apiece, plus two or three bucks for shipping via first class mail to the USA. I did notice that when United Nuclear (in the USA, and they do tend to be kinda pricey) has them in stock, they sell them for about $30 apiece! Wow! In contrast, I have often found Euro vendors and Hong Kong vendors selling them online for six US dollars!

 

Interesting, i havent found any on ebay just the usual $30 deals online. I have a ton of the actual tritium paint in different colors which i purchased about a year ago for my gun sights. The stuff is very cool and very bright even in daylight.

There are a couple of Ebay vendors selling them right now, as tritium glowrings, for prices ranging from 2 for $25 to about $18 apiece.

 

There is also an Ebay vendor selling the smallest size of the bare glass vials for $7 apiece, but these are rather tiny and not very bright!

[+Vinny & Sue Team]

Oops! Forum burp... double post!

Edited October 9, 2008 by Vinny & Sue Team

[+trainlove]

P.S. Along the lines of a prior posting, http://forums.Groundspeak.com/GC/index.php?showtopic=200336

I have not been able to detect any damage to the polycarbonate outer plastic shell of these. But I do not have a control, unirradiated, one to compare it to. I guess the glass inner shell DOES stop most of the radiation.

Or my other tests, with Americinium 241, has a much higher irradiation potential at the infinitesimal distance betweeen the raw isotope and the plastic, i.e. nearly infinite radiation density.

[+Vinny & Sue Team]

I have received requests from some local cachers, asking if there is some way that they can get their hands on one of these things really quickly! Here is the response that I sent to one of them via my local MGS forum:

 

If you really really really really really need one very badly, I will be happy to award one (the larger and brighter type that has the glass capsule embedded in a polycarbonate outer shell; my choice of color, but probably blue or red) as a prize to the first person who logs a valid find on Psycho Urban Cache #13 - Impossible - Give Up Now! (located in Maryland) or Psycho Urban Cache #14 - Cliffside Catacombs (located in West Virginia) or Psycho Backcountry Cache #3 - Bitch Creek Crossing (located in Idaho, near the ID/WY border) between now (3:13 PM, 10/09/2008) and midnight Saturday night (midnight on Monday, 10/13/2008; I extended the offer to the 13th, since Monday is a federal holiday.)

 

P.S. I might also give one to the first person who introduces me to a really cute jenny donkey, or to The Fifth Element, aka Milla Jovovich!

 

.

[+9Key]

I have received requests from some local cachers, asking if there is some way that they can get their hands on one of these things really quickly! Here is the response that I sent to one of them via my local MGS forum:

 

If you really really really really really need one very badly, I will be happy to award one (the larger and brighter type that has the glass capsule embedded in a polycarbonate outer shell; my choice of color, but probably blue or red) as a prize to the first person who logs a valid find on Psycho Urban Cache #13 - Impossible - Give Up Now! (located in Maryland) or Psycho Urban Cache #14 - Cliffside Catacombs (located in West Virginia) or Psycho Backcountry Cache #3 - Bitch Creek Crossing (located in Idaho, near the ID/WY border) between now (3:13 PM, 10/09/2008) and midnight Saturday night (midnight on Monday, 10/13/2008; I extended the offer to the 13th, since Monday is a federal holiday.)

 

P.S. I might also give one to the first person who introduces me to a really cute jenny donkey, or to The Fifth Element, aka Milla Jovovich!

 

.

Donkey on the way!

[+magking1971]

After a large search, all places I found that sold them they are sold out.

Edited October 9, 2008 by magking1971

[+Vinny & Sue Team]

After a large search, all places I found that sold them they are sold out.

Much in line with what I mentioned earlier, it appears that there are a number of vendors selling them online at this moment who have them in stock, including two Ebay vendors (one via auction, the other an Ebay store); some of them call them "tritium glowrings", while some call them "tritium glow sticks".

 

Of course, when the vendors start calling them "glow sticks", you need to be a bit careful to be sure that you do not accidentally purchase the much larger chemical glowsticks, which glow for only a few hours once activated, since they both go by the same name, but the chemical glowsticks cost only about 90 cents apiece (and are much larger.) And, if you are looking for gizmos sold under the name "glowsitcks", you will also want to be sure that you do not accidentally buy the little things that sell for $1 to $3 apiece, but which do not contain tritium at all, and rather, are simply a so-called luminescent/phosphorescent plastic, the type that glows in the dark for four hours after having been exposed to light (like the buttons on some handheld TV remote control devices.)

[+Mr. 0]

If I eat a frozen burrito straight from the freezer, then ingest the tasty goodness inside one of these, will it cook the burrito in my belly? And do these come in different flavors, such as nachos and cheese to compliment my burrito? It seems it would be a time saving measure, what with not having to deal with the pesky microwave oven.

 

Seriously though, I can see where these could be applied to various caches where fire tacks and such just wouldn't work (inside caves, tunnels, etc, as you mentioned), though I've not heard of them being used in any. I think that if one can find them cheaply enough, they would cost less over time as compared to other light emitting devices, when taking into account the device, batteries, and time to maintain them.

[John E Cache]

These lights remind me of fractal's radioactive balls. They are made of vaseline glass and only glow uner a black light, though.

[+TexasGringo]

***If I eat a frozen burrito straight from the freezer, then ingest the tasty goodness inside one of these, will it cook the burrito in my belly? ***

 

No but it does wonders on hemmorids.

[+Vinny & Sue Team]

***If I eat a frozen burrito straight from the freezer, then ingest the tasty goodness inside one of these, will it cook the burrito in my belly? ***

 

No but it does wonders on hemmorids.

Hmmm... interesting... I never mind an appropriate amount of "topic drift", as that is what breathes life into threads and topics, and allows exploring all kinds of new things, but what I do find interesting in this case is that almost all of the responses so far, while fun, have been of the somewhat-off-topic variety. So, I must assume that no one has yet encountered a cache using GTLS, nor has anyone here ever created a cache using GTLS.

 

Frankly, I am surprised at this fact, because GTLS devices are fairly well-known, and they offer features unavailable with any other extant technology. I am still hoping that we will see at least one or two posts from folks who have actually encountered a cache which uses GTLS, or who has created a cache using GTLS!

[+Kit Fox]

Hmmm... interesting... I never mind an appropriate amount of "topic drift", as that is what breathes life into threads and topics, and allows exploring all kinds of new things, but what I do find interesting in this case is that almost all of the responses so far, while fun, have been of the somewhat-off-topic variety. So, I must assume that no one has yet encountered a cache using GTLS, nor has anyone here ever created a cache using GTLS.

 

Frankly, I am surprised at this fact, because GTLS devices are fairly well-known, and they offer features unavailable with any other extant technology. I am still hoping that we will see at least one or two posts from folks who have actually encountered a cache which uses GTLS, or who has created a cache using GTLS!

 

I have several ideas about using specialty items for geocaching. Prohibitive cost, and risk of theft have swayed me against implementing several of my ideas. Another issue is the lack of cachers interested in finding unique caches. My night caches get long and super nice found it logs, but they only get finds once per year, or less.

 

I've hidden two caches requiring the use of a black light, and they have had only a couple of finds in two years.