Talk:Tritium radioluminescence

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Decay rate

It has a half life of about twelve and a half years. Thus, any traser will lose half its brightness every twelve and a half years.

This seems logical enough, but it assumes the relationship between the number of tritium atoms and the brightness is linear. Is it? - furrykef (Talk at me) 15:32, 13 October 2005 (UTC)

It is very close to linear. +sj + 07:14, 2 May 2006 (UTC)

It is a linear relation. Every tritium atom has the possibility of decaying, so the number of decays is directly proportional to the number of atoms - bar tiny statistical variations. —Preceding unsigned comment added by 94.168.48.161 (talk) 16:41, 22 April 2010 (UTC)

Very close to linear is more correct. The visible light results from excitation and spontaneous emission of phosphor (or other suitable material). Since the amount of phosphor in any device is finite, the relation isn't truly linear, but for most devices, I assume we are near the linear limit. 86.145.250.191 (talk) 21:16, 29 March 2011 (UTC)

Actual half life in terms of luminescence will always be less than twelve and a half years. This is due to two basic factors. Firstly tritium is introduced to the GTLS by evacuation of air from the GTLS capsule then introduction of tritium usually by heating a bed of uranium tritide in a vacuum system. Economically it is not feasible to evacuate the phosphor coated GTLS capsule to less than 0.0000001mm Hg. This leaves sufficient oxygen for some interaction of tritium (a hydrogen isotope) to water; although in minute quantities. But this will also cause a second factor that phosphors are sensitive to water and their performance also degrades. This second factor is dependent on the phosphor type. The typical green phosphors are based on copper infused zinc sulfide which tends to have higher resilience than orange/yellow cadmium infused zinc sulfide phosphors. Realistically a ten year half life for a well produced green GTLS would be matched by seven years for an orange/yellow device. There are many other factors that have some influence on performance of GTLS's such as the decay product for tritium is helium-3 and the associated volume relationship (1 atom of tritium decays to two atoms of helium-3)etc. As author I worked in a technical capacity for a manufacturer of GTLS's for 20 years — Preceding unsigned comment added by 86.160.121.223 (talk) 15:41, 16 October 2011 (UTC)

LEC

"light-emiting capacitor" do these exist? this page is the only google link for it —Preceding unsigned comment added by 67.169.118.97 (talk • contribs)

See the following links:

• E-Lite Technologies Inc
• LightPanel
• Energy Exit — ACF NewSource

— Johan the Ghost _seance 09:25, 26 July 2006 (UTC)

• "LEC" is a term used by the Ceelight company to describe their flat panel lighting products. They make Electroluminescent derived lighting products , but strongly object to the products being called electroluminescent. I think of this as being a marketing decision, but figure they can call their product what they want. I was rather surprised to see the phrase tucked into the traser article, since they are not self powered and have absolutely nothing to do with the article.--Ken McE 17:21, 28 November 2006 (UTC)

Similiar lamps filled with Krypton 85 or using Promethium

There are similiar lamps filled with Krypton 85 or using Promethium compounds as radioactive source. Who knows more about them? —Preceding unsigned comment added by 89.49.75.207 (talk • contribs)

• You can use any beta emitter to make a traser. H3 get used a lot, probably because it is the least deadly if spilled.

--Ken McE 17:23, 28 November 2006 (UTC)

Tritium

This entire page is about tritium. Why is it called "Self-powered lighting"? I couldn't imagine a more vague and less descriptive article name.

• That phrase is in public use to describe this technology. It denotes equipment that contains its own power and needs nothing from the outside world. If you have a clearer phrase, please feel free to post it here.--Ken McE 17:26, 28 November 2006 (UTC)

Patent ref removed

Removed reference to a specific patent relating to a product not currently in production, as this appeared to be advertising. —Preceding unsigned comment added by 94.168.48.161 (talk) 16:28, 22 April 2010 (UTC)

Traser

The article titled "Traser" redirects to this page. This page doesn't explain anything to do with Traser. It doesn't even contain the string "Traser" anywhere on the page. Why is this?

The google definition shows that a previous wikipedia article had a proper definition, but it has since been vandalized: http://www.google.ca/search?hl=en&q=define%3A+traser

• ::The author "UninvitedCompany" did an edit on 19:10, 24 March 2006, it appears that he considers the word "Traser" to be copyrighted. I had thought the word dated back to NATO in the 1960's, and that they used it as a generic description of the technology.--Ken McE 17:31, 28 November 2006 (UTC)

Regulation

Because these devices are radioactive, in some places (in the US) their use is restricted or prohibited. There may be special disposal requirements, as hazardous waste. Proper disposal may be expensive. EXIT signs are commonly offered using this technology, and reading about them is a good way to learn about possible restrictions and costs. Please add information about regulation in various countries and states.-69.87.201.141 11:03, 12 May 2007 (UTC)

Personal research, in health section

This was in the 'health' section, and really shouldn't have been, for lots of reasons:

Quote: Tritium presents no external radiation threat when encapsulated in non-hydrogen-permeable containers. This is not strictly true. I have observed someone testing my Tritium keyring with a hand-held X-ray detector. It gave an indisputable reading. The explanation - electrons hitting a target create X-rays. Unfortunately, I don't have the actual reading and I can't go back to repeat it. Perhaps someone could test this and supply the facts. —Preceding unsigned comment added by 68.116.67.106 (talk) 10:19, 3 November 2007 (UTC)

Interesting. I noticed this effect even with an expired lamp. Still glows a bit, maybe made in the mid 1990s. I am testing it with a heatshrink wrapped glass mantle tube of the type used in older model dosimeter, at a reduced voltage. 78.111.195.1 (talk) 08:31, 24 September 2023 (UTC)

Reference 4 has a dead link.

Beta lights

Theyre aka beta lights, so this term should be slotted in there somewhere. Tabby (talk) 01:01, 24 December 2007 (UTC)

NRC Regulation Document

Maybe someone can interpret this more clearly for me, but according to NRC 10 CFR §30.19, a reference which I have just added to the article, tritium "used in products primarily for frivolous purposes or in toys or adornments" are not exempt from nuclear licensing requirements. Therefore, tritium-powered keychans, zip pulls, and other such devices would technically be illegal US-wide if bought without the respective license application. So I think that means the sentence that asserts "[tritium products] are readily sold and used in the US" should be removed. In addition, at least one Australian seller on eBay refuses to ship his wares to the U.S. for fear of repercussions. Luinfana (talk) 18:20, 19 December 2008 (UTC)

I disagree. Tritium products that are not primarily for frivolous purposes or in toys or adornments ARE readilly sold in the US. They are just not permitted in toys and the like. I am uncertain whether a tritium impregnated zipper pull would be considered frivolous. Of more concern to me is that the citation you placed does not address the request for citation you removed. The request for citation was next to and therefore referencing the assertion that devices containing tritium are illegal for export from the US. Your citation does not reference that at all and so I have reverted the article to its previous state. Pzavon (talk) 02:39, 20 December 2008 (UTC)

Ah, I apologize then. I'm still not crystal clear on what that regulation entails, but I thought it at least addressed the export laws. If it doesn't, then you're right, it shouldn't replace the request for citation. However, I do believe tritium zip pulls, keychains, and the like are considered "frivolous uses," not because they are "toys," but because they are "adornments." Luinfana (talk) 17:22, 20 December 2008 (UTC)

After reading the citation you provided (it is only 3 paragraphs) it was very clear that it did not cover exports since the word "export" never appeard there. I am not certain whether a zipper pull would be considered frivolous, either. But I could make an argument that it is not simply an adornment as the flourescence makes it easier to find in the dark. In either case, a citation that it would be considered frivolous should have been included with your example if that is the case. Pzavon (talk) 16:23, 21 December 2008 (UTC)

FYI, Theodore Gray (an expert on elements, of "Periodic Table Table" fame) contends that tritium keychains and the like are indeed illegal in the U.S. unless the owner certifies that they will be permanently affixed in a stationary location. It would seem, then, that such a restriction invalidates the very purpose of such devices. Noir (talk) 03:49, 28 December 2008 (UTC)

Well, I could argue with your characterization of him as an "expert on elements", at least on the basis of his biographical article in Wikipedia, but it really doesn't matter. What is needed is an expert in NRC regualtions, and he is clearly not that. So you have the opinion or one non-expert (Gray) and another non-expert (me) saying that an agrument could be made on the contrary side - which it could. I'm not asserting that such an argument would necessarily succeed. That requires the expert on NRC regs, or better yet an interpretation from NRC. Going further in your comment, restrictions that invalidate the purpose of a device are not uncommon. That is what you do when you say such a device cannot be used. Pzavon (talk) 01:58, 30 December 2008 (UTC)

Oh, I agree with you on almost every point. You're absolutely right, a NRC interpretation would be required to fully comprehend this. If you're interested in Mr. Gray's status as an expert on elements, though, I suggest you take a tour of his website rather than the Wikipedia article, which is quite limited and doesn't give much information about him. He also authors a monthly Popular Science column and has appeared on National Public Radio, etc. Mainly I think his comments are relevant because he claims to have actually went through the process of registering his periodic table as a permanent location for a traser sample. But again, yes, a NRC guru would be the real expert. Noir (talk) 18:36, 1 January 2009 (UTC)

Moved to Tritium illumination

Sorry to be so abrupt but hopefully the move summary will explain: 1. Self-powered lighting doesn't appear in the sources and tritium illumination does. 2. Self-powered lighting is too vague as it could also mean Chemiluminescence among other possibilities. Anynobody(?) 04:47, 11 May 2009 (UTC)

Proposal to merge with Radioluminescence

Should probably be rejected because there is more than one source of radioluminescence. For example Radium and arguably Čerenkov radiation. Anynobody(?) 04:55, 11 May 2009 (UTC)

I've taken off the tag. Radioluminescence can also talk about radium watch and clock dials. --Wtshymanski (talk) 07:46, 22 December 2009 (UTC)

That there is more than one type of radioluminescence isn't an argument for not classifying an example of a type of radioluminescence as radioluminescence. The radioluminescence of Tritium is not a unique case, and it would be sensible to classify it with similar examples. —Preceding unsigned comment added by 94.168.48.161 (talk) 16:32, 22 April 2010 (UTC)

Use of non-gaseous tritium

The article does not seem to make any mention of tritium paint in which a non-gaseous tritium compound (such as a tritiated polymer) is mixed with a phosphor (such as ZnS). It is unclear if the watch face illustrated uses a paint of this type, or if the lights are tiny vials of gaseous tritium. The discussion of night sights is similarly unclear. As I understand it from perusing various websites, this sort of paint is in use for these purposes, so presumably it is not the same stuff as is described under "Self-luminous microspheres" (of which "no actual paint is known to have been produced yet"). Clarification of these points would be good. If the article is supposed to include the use of non-gaseous tritium for illumination then the opening sentence ("is the use of gaseous tritium") needs changing. 86.161.42.61 (talk) 20:54, 19 March 2010 (UTC).

I know I'm replying to something years old, and I'm using personal research, but for the benefit of future generations who pass this way: basically every watch you find these days that has tritium illumination, uses the tiny vials, not the paint. Including the watch (currently) pictured in the article; looking at the largest version of the image, you can see that the tubes have a thickness, and a flattened-round cross section - you can see the "end" of some of the tubes clearly.

I imagine that at least part of the reason the tube approach is more popular is that there would be much less regulatory paperwork to go through (the watch manufacturer is simply incorporating sealed GTLS vials that already have some sort of certification, rather than painting radioactive - however minute the quantity - paint onto their dials and watch hands and then having to get each watch body design certified as a proper container for the radioactive paint's emitted radiation). They also wouldn't have the difficulties of dealing with an open source of radiation - the paint - in the factory and manufacturing process, which would likely include sealed systems for applying the paint and some sort of decontamination and storage/containment process for the various delicate parts (watch dials and hands) coming out of the painting system. The paint would also be (technically, at least), a hazard, and regulatory problem, to anyone opening the watch for service (thus, "need a new battery? have to send it back to the factory and their secure/clean-room facilities"). In a lot of ways, the GTLS vials have made tritium-illuminated watches practical (in a world that concerns itself with the hazards/consequences of the materials used - for enlightening/frightening reading on pre-concern days, look into the Radium Girls). (And no, I have no connection to the related industries - I just have a watch with tritium illumination - an old Traser P5902 - and I find the technology fascinating.) CarlRJ (talk) 01:23, 28 July 2014 (UTC)

Yes, it would be good to have the article confirm that all these products, including the pictured watch, use the encapsulated gas. Are there regulations that prohibit non-gaseous tritium products ? Some indication of who makes these tubes, and how would be interesting. Rod57 (talk) 12:33, 22 February 2020 (UTC)

Oh, and there's also mention in some places of vials of liquid T2O... 86.161.42.61 (talk) 21:12, 19 March 2010 (UTC)

Bremsstrahlung causing possibly harmful ionizing x-rays

Hey there. In the discussion to the corresponding article in de.wikipedia.org has been mentioned briefly: While the beta-rays may be not harmful, the resulting bremsstrahlung would partially be in the ionizing x-ray spectrum. These x-rays probably would probably escape the housing and may be harmful on the long run. I unfortunately cannot confirm any of this, but maybe some geek could to the math. --92.201.69.64 (talk) 00:21, 31 August 2011 (UTC)

It should be no worse than a 18 kV x-ray tube, with the current of ~ 10 nano amperes for each Curie of tritium (calculated by multiplying the decays per second by electron charge, and by two for both inner and outer bremsstrahlung). Overall it ought to be less dangerous than a CRT TV, but I am not sure how much thick lead glass used in CRTs helps with the shielding. 78.60.253.249 (talk) 17:27, 26 May 2013 (UTC)

For what it's worth (as personal research/unsubstantiated hearsay), a friend of mine got a keychain fob that consisted of a hard plastic tube containing a tritium vial. Her husband, whose work involves machinery for detecting minutes trace of radiation, took it to work and scanned it with said machines. He then returned it to her, unconcerned that it would pose any hazard. I don't recall what, if anything, was detected, but it was clearly not at any level that could present a problem. CarlRJ (talk) 01:35, 28 July 2014 (UTC)

Either that or he took out a large life insurance policy on her :) 116.231.75.71 (talk) 08:32, 18 February 2018 (UTC)

Citations Removed

Why has my citations been removed? — Preceding unsigned comment added by Sabastian130 (talk • contribs) 10:08, 29 May 2013 (UTC)

You have already been told why and you are pretending you haven't heard. --Epipelagic (talk) 17:04, 29 May 2013 (UTC)

/* Safety */ Deleted description of HTO reacting with skin oil

"Persons working with the gas face another hazard: tritium reacts with the oxygen in air, forming tritiated water. This moisture is readily ingested by the body. When in contact with any hydrocarbon the tritium atom replaces the natural hydrogen. This can even occur with the natural oil on a person's skin."

The body will excrete HTO, it doesn't accumulate. HTO is not fat soluble but has the same chemical properties as H2O. Science blessCircuitboardsushi (talk) 02:42, 14 January 2017 (UTC)

Phosphorescence

"The tritium in a gaseous tritium light source undergoes beta decay, releasing electrons that cause the phosphor layer to fluoresce."
Wouldn't the phosphor layer—per definitionem—phosphoresce rather than fluoresce? Fwbeck (talk) 06:26, 22 August 2017 (UTC)

See: Persistent luminescence. Aspro (talk) 14:24, 22 August 2017 (UTC)

GTLS experiments

Some expired tritium GTLS lamps with an unusual geometry (pinched off rather than laser sealed) can respond to RF standing waves similar to a neon or argon tube causing the light output to increase by a factor of 10, with the latter effect being part of an experimental quantum sensor due to the advantageous location of the 1.5 to 1.6 GHz self resonance being in the range of most SDR units if the lamp is placed in a silver resonance chamber open at one end. This is as of yet impossible to replicate but mentioned here in the hopes of further experimentation by researchers. 78.111.195.1 (talk) 02:24, 9 October 2023 (UTC)