There are a number of threads that touch on this issue and invariably recoil then lapse into silent indecision. Let’s call this one the rectal digital examination of historical aviation that could manage a prostrate issue, but ends up being not done, to be faced ‘another day.’ In simple terms radium emits radiation which excites luminescence from the zinc sulphide in dial paint. Over decades the zinc sulphide breaks down and the dial paint no longer glows. The radium component, however, continues to emit radiation. If you ingest old dial paint or dust by opening a gauge, into your lungs or mouth via your fingers, you ingest a harmful radioactive substance. Never open a gauge or trifle with dial paint. The radium emits in all directions. Therefore, over decades, the aluminium of the gauge face, or the innards of the gauge may become irradiated. So the proper delousing of your gauge needs a thoughtful approach. In the end, a thoughtful approach means proper delousing will cost money. That means a small group of rare gauges might be treated and certified, while a larger group of gauges will not. I know of no service that will do this, given the cost of disposal for radioactive waste and the cost of safe infrastructure to treat gauges without harming personnel exposed to this task for 8 hours per day. These costs intersecting with a large body of collectors without the funds to support such an initiative. Perhaps Museums have funds to do this properly, but not the space in budgets. There is an opportunity for somebody to set up the right service, based on bulk servicing of a number of Museums, in order to create the cashflow to sustain the right type of solution. Ie, get 10 Museums to agree to treat 100 gauges each, 2 per month for 4 years, and use this bulk order to set things up properly. Then individual collectors could piggy back on this with individual gauges, if the economics stack up. In simple terms a certified, treated gauge would have more value, and more future, than one that is not. Until such a solution is available, like Walt Disney in cryogenic storage, do not disturb any gauge.