Just finished reading several articles about handling radium instruments, and have found the following information regarding Radium 226 components in the U.S.
Radium paint consists of Radium226, Phosphor and a binding agent. The radium excites the phosphor, making the paint glow. The fluorescent qualities of the phosphor usually wears out after 20 to 50 years. Radium paint that no longer glows is still radioactive. The half-life of radium226 is about 1,600 years. Radium paint was still in limited use through the 1980's, mostly in military applications.
The is no specific U.S. regulation forbidding the possession or use of radium aircraft instruments
that are sealed in a private vehicle or a private collection. There is a limit of 100 units in a single facility or location without a special license/permit.
Any broken or unsealed radium instrument is considered a hazard and by law requires special handling, usually by a properly licensed instrument repair facility or hazmat operator. Disposal is only allowed at a licensed hazardous waste facility designated by the NRC.
Some sealed radium instruments may escape detection because the case and glass are sufficient to block alpha and beta particles, and gamma radiation is at or below background radioactivity levels. If these are opened, they could present a hazard.
Other sources of radium paint can be found on vintage panels and radio components, mostly lettering and dials. These are considered to be the same as a damaged or open instrument.
In general, Turn and Bank Indicators (Ball and Needle) have the most radium paint in them by volume.
For the most part, there isn't a cadre of federal agents looking to raid your hanger over a couple of vintage instruments. For the 99.9% of owners, there little or no concern of ever having a problem with the authorities.
How to get into trouble with radium instruments.Keep more than 100 in a facility without a special permit/license. (A 'facility' can be a group of buildings near each other.)
Keep any radium instrument that is broken or disassembled`. (There are guidelines for storing these while awaiting proper disposal.)
Throw any radium instruments, parts or materials in the garbage or introduce into the sewer system. (Fines or worse.)
Import radium instruments from outside the US. (A good way to attract unwanted attention from Customs.)
Advertise that you have "tons" of vintage instruments for sale. (Authorities do scan social media.)
Safety PrecautionsStore radium instruments in a secure area away from places frequented by visitors or workers. Exposure rates drop dramatically for Alpha and Beta particles with distance and obstructions. (A single page of typing paper will stop an Alpha particle.) Distance reduces Gamma ray exposure exponentially.
Place any broken instruments or disassembled components in a sealed, airtight container and store as above until you can arrange for approved disposal.
Use a Geiger counter to test suspect instruments, or place a dosimeter among instruments in storage and check regularly.
If handling suspected material, wear rubber gloves, goggles and a painter's particle mask. Disposable clothing, like a paper painters coverall, is a good idea. Dispose of these the same as for an open/broken instrument.
If you have more than fifty radium instruments, keep a record of them by description, part number and serial number and keep them secured. If you are ever questioned, showing you have accounting and control over those items goes a long way to satisfying the authorities you are taking necessary precautions.
Want to know more? Check this article..
http://www.aia.net/pressroom/radiumdialnews.htmlWarbird owners, by nature, are collectors of lots of vintage and 'neat' parts and components, and some may be unaware of the implications of storing and handling of radioactive components. Just a little common sense and knowledge will help keep things safe, and out of trouble.