Because sources often resemble other material, (such as steel) or are encapsulated in steal, they can be mistaken for being not radioactive. As a result, incidents have occurred where sources were disposed together with other refuse. Other incidents occurred where staff found radiation sources amongst other old or abandoned equipment. Theft of sources incidents has also occurred, unknowingly to the thieves.
The human causes of lost, stolen or found sources include:
- Outdated inventory
- Unaware of source: workers are unaware that a piece of equipment or apparatus is a radiation source. As a result it may be lost (misplaced or discarded), because inadequate security measures have been applied.
- Cars stolen: incidents have occurred where thieves have stolen a vehicle which contained a source in the car boot or utility tray.
- Signage: often the hazard signs used on the source are incorrect meaning that staff are unaware of the risk.
Organisational issues include the following:
- Not providing training to staff: staff are provided with little or no training on what radiation sources are in their workplace and what controls need to be implemented.
- Not providing adequate systems: the organisation did not ensure that they maintained an adequate radiation source inventory and did not have systems in place to correctly label sources.