A control monitor is sent with each group of personal monitors to measure background radiation.
The occupational dose for a worker is calculated by subtracting the ‘background’ radiation of the control monitor from the worn workers monitor. This calculation is conducted by the PRMS.
Any reading from a personal monitor that is above that of the control is assumed to be due to occupational exposure.
Storing your control monitor
You should store the control monitor together with the wearer monitors when not in use, at a location in your workplace that is not exposed to radiation from materials or apparatus used.
Good practises for storing wearer monitors and controls:
- Stored in a common area with easy access for all wearers
- Stored in a place that is representative of the area (not a lead lined box)
- Separate controls for different buildings or floors
- Away from walkways where radiation source may transit
We cannot inform you exactly where to store the control monitor as we are unfamiliar with your workplace. This decision should be made by the workplace’s RSO and/or WHS Co-ordinator as they will be more familiar with the workplace.