Tritium activity ?

Greetings from Germany.

I can't find informative search results about this.
So many users here have this nice tritium vials in their flashlight pistons, i'd like some too ! :laughing:

Wikipedia.org knows something, but not enough.
The german and english article are not the same.

"Die Aktivität von Glowrings beträgt bis zu 17,5 GBq"
"The activity from glowrings is up to 17,5 GBq"
says the german wiki. They used a trigalight glowring for measuring, it should be the same as the Nite glowring.
Since i'm not a scientist, i have no idea what this GBq means or how to measure it.

"Die Aktivität von Uhren mit Tritiumgaslichtquellen liegt in der Regel unter 1GBq."
"The activity from tritium-wristwatches is usually lower than 1 GBq."

For civilian, everything above 1 GBq is illegal.

Well at least i got a number to work with.
Any idea how much of this GBq activity you can measure from a tritium vial ?
And if it's above 1 GBq, how can i lower the activity to get this little light legal here ?
I am thinking of my Nitecore, if i had a slot in the piston and the tritium vial glued into it, could i fill the slot with more glue or anything transparent to lower the activity ? I'd also like that for safety reasons. I droped my flashlight in the past, i bet it's gonna happen again.

I hate trouble with german law, they take everything soo serious, that's why i'm asking...

Rawk said:

Greetings from Germany.

I can't find informative search results about this.
So many users here have this nice tritium vials in their flashlight pistons, i'd like some too ! :laughing:

Wikipedia.org knows something, but not enough.
The german and english article are not the same.

"Die Aktivität von Glowrings beträgt bis zu 17,5 GBq"
"The activity from glowrings is up to 17,5 GBq"
says the german wiki. They used a trigalight glowring for measuring, it should be the same as the Nite glowring.
Since i'm not a scientist, i have no idea what this GBq means or how to measure it.

"Die Aktivität von Uhren mit Tritiumgaslichtquellen liegt in der Regel unter 1GBq."
"The activity from tritium-wristwatches is usually lower than 1 GBq."

For civilian, everything above 1 GBq is illegal.

Well at least i got a number to work with.
Any idea how much of this GBq activity you can measure from a tritium vial ?
And if it's above 1 GBq, how can i lower the activity to get this little light legal here ?
I am thinking of my Nitecore, if i had a slot in the piston and the tritium vial glued into it, could i fill the slot with more glue or anything transparent to lower the activity ? I'd also like that for safety reasons. I droped my flashlight in the past, i bet it's gonna happen again.

I hate trouble with german law, they take everything soo serious, that's why i'm asking...

Click to expand...

1 GBq is about .27 curies. From that it is possible to back into how much Tritium that really is.
1 curies is the rate of disintegration per second from 1 gram of radium. We can then determine how much Tritium that is by comparing the half lives
Ra 226 half life is 1620 years
H 3 half life is about 12 years,
so you need 12/160 x the number of Tritium atoms for 1 Curie of Tritium or 1/135 as many. However the weight will be proportional to the atomic weights,
so we get 1/135 x 3/226 x 1 gram =~.1 milligrams


Under standard conditions that would be 22.4 x .0001/6 liters of gas or about .37 ml.
That is probably quite a few Tritium vials.


While Tritium is very radioactive (it has a short half life), the decay product is a relatively low energy electron (20KEv). So as long as you don't breath it, or otherwise get it into your body, it is harmless. The layer of dead skin on your body is more than enough to stop the 20KEv Electron.

If you break the vial, leave the room. H3 is still much ligher than air, so it can be expected to diffuse, and rise in the atmosphere fairly quickly.

Some types of Tritium vials may spring a leak. This happens because the trititum has been made into a hydrogen compound to make it easier to handle. If the package that holds this compound is sealed, it may be a problem eventually. The Tritium decays into Helium 3, so gas is evolved that usually must be vented. However the nature of Helium is such that in most Tritium vials, the Helium atoms are so small that simply can diffuse between the glass atoms that hold it as fast as it is generated.

Someone probably should double check my math, but I think it is correct.

Thank you very much !
:thumbsup:

Will the vial break when the flashlight falls on the ground ?

Rawk said:

Will the vial break when the flashlight falls on the ground ?

Click to expand...

Not if the vial is inside a slot, like the one you often find on a piston or the tail of many lights. If you just glue it on the surface of a flashlight, it can be easily cracked.

Generally, the vial is held in place with a strong glue, often some NORLAND 61 or a clear epoxy. It should be completely covered inside a slot or groove to be well protected. If it's done that way, it almost unbreakable since it is well protected.