Radiation safety – The need for identification and management of radium luminous devices
by Jennifer Pyne, Canadian Nuclear Safety Commission
Until the 1960s, various artifacts such as consumer and military products – like wristwatches, clocks, marine compasses and aircraft instruments – were manufactured using a radium based, glow-in-the-dark paint. These products are called radium luminous devices.
The most common radium luminous devices that may be seen today are historic aircraft instruments, and many of these can still be found in Canada. Although the radium remains radioactive for thousands of years, the paint in these devices usually breaks down chemically after several years, and may no longer glow in the dark. When new, the radium luminous paint was often white, but typically tarnished to yellow as it aged.
Radium luminous devices pre-date the regulation of nuclear substances, and are generally not identified or marked as containing nuclear substances. As long as the devices remain intact, the risk of contamination is very low. If the device is open or damaged, the radium inside may present a radiological risk if ingested, inhaled or absorbed through an open wound in the skin.
Radium luminous devices sometimes inadvertently end up in scrap metal recycling facilities, where they set off the alarms on vehicle radiation portal monitoring systems. Although not required by CNSC (Canadian Nuclear Safety Commission) regulations, many recyclers have installed these radiation portal monitoring systems, to screen waste before committing it to landfills, or before compacting it for transport to landfills or to other recycling facilities.
If any of these devices are discovered at recycling facilities, the CNSC is available to provide advice on the identification and management of radium luminous devices. A poster and pamphlet – published in 2011 on the CNSC website – would also be of particular interest to recycling facilities. Hard copies of the material, as well as Alarm Response Guidelines for Radiation Portal Monitoring Systems, are available by contacting [email protected].
For information on identifying and removing radium luminous devices from scrap metal recycling facilities, or from public and private properties, contact the CNSC at 1-800-668-5284, or email [email protected].
*Reprinted with permission from the PROMPT, Newsletter of the Canadian Association of Recycling Industries, Volume 3, No. 12, December 2011.