Well, as I've been caught
in flagrante spouting bolleaux here is a clip from the dreaded HSE on the very subject to make amends.
VINTAGE AIRCRAFT RESTORATION
Recent inspection activity in the aerospace and industrial radiography industry has revealed that those engaged in the restoration of vintage civil and military aircraft are largely unaware of the radiological risks involved in their work.
Many aircraft, but mainly those built before circa 1950, have instrument dials luminised with radium paint. Dose rates on contact with these instruments can sometimes exceed 200 μSv h-1 β/γ (e.g. Seafire fuel gauge) and dose rates in the pilot's position may be as high as 15 μSv h-1 β/γ (e.g. North American Harvard). If the instruments are taken apart there may also be a significant contamination risk and, in enclosed cockpits or storage areas, radon exposure may be significant.
A risk of significant radiation exposure to those restoring, maintaining and flying such aircraft, and those visiting museum cockpit exhibitions, therefore exists although, for the most part, those carrying out such activities are unaware of those risks.
The HSE will be exploring ways to further publicise and research the problem. In the meantime the following steps can be taken to reduce likely exposures to levels which are as low as reasonably practicable. In all cases, however, the advice of a suitable radiation protection adviser should be sought.
1. A risk assessment should be undertaken and a radiation survey of the instruments and cockpit should be performed. Where dose rates in excess of, say, 2.5 μSvh-1 β/γ exist at the pilot's position, steps should be taken to reduce radiation levels and/or prohibit access by members of the public. Simple measures such as replacing the instrument glass with a thicker variety (provided there is no likelihood of contamination), or the replacement of switches etc. with newer types, may be reasonably practicable.
2. When not in use or installed in the aircraft, instruments should be stored in sealed plastic bags. Checks for loose contamination should be undertaken when the instrument is overhauled or fitted in the aircraft. Where large numbers of instruments are stored together checks on radon levels will be appropriate.
3. When maintaining or overhauling instruments care should be taken to avoid the spread of contamination or possible personal contamination. They should only be handled when wearing appropriate gloves and, where there is evidence of paint flaking, a simple dust mask should also be worn.
4. If it is decided to replace the instrument and to dispose of the radium luminised item, a specialist company must be used for the disposal of radioactive waste. There are only a small number of such companies operating in the UK, these include: Safeguard International Ltd (01235 435795) and Active Collection Bureau (01795 437001). There are currently some difficulties over the disposal of radium in the UK and some delay in disposing of the item may be experienced, and it may be necessary to store the items in the meantime.