I have to confess that when I saw the word’s ‘Tritium Vial’ I had to go to DuckDuckGo to see what was meant. Of course I knew what ‘Tritium’ was ever since watching the ‘Heroes of Telemark’ and similar WW2 exploits aimed at crippling Germany’s ‘heavy water’ production.
Like Deuterium, Tritium is an isotope of Hydrogen and is mildly radioactive – though in such tiny (trapped) quantities as these minuscule vials it is nothing to worry about – any more than smoke detectors which also contain a tiny (trapped) quantity of radioactive material. If you worry about such things bananas probably contain more (free) radioactivity. Yes, this is true.
However, it had not occurred to me that you could utilise the small amount of energy from this radioactive decay to produce light but that is just what these tiny vials do. They glow in the dark and will continue to do so for decades but the light will not be enough to read a newspaper by.
It will be enough though (when attached to desired objects such as your glasses etc) that you will be able to find them in the dark – which is really quite handy when you are hiking. You can glue them to things or make small slots for them to fit into in your equipment. They are readily available.
Unfortunately Tritium is one of the rarest substance on Earth and is worth over $30,000 per gram so the tiny amount in these vials makes them fairly pricey $20-50ea say depending on size. For example three of these 22.5 mm long ones cost A$75.79 (Dec 2021). Still for the Xmas present for the ultralight hiker loved one who already has everything no price is too great surely?
Day
Night
At the moment this is my favorite torch:
20 Gram Rechargeable Head Torch + Lantern
