Description of the incident
Two teams of industrial radiographers were working on a new installation, both inspecting welds using 160 kV x-ray machines. One worker was setting up the x-ray tube to carry out an exposure when his colleague, some distance away at the control point, energised the machine, exposing the worker to x-rays. His colleague at the control point had heard a shouted request to switch on the x-ray set – however this request was shouted by the other radiography team.
The radiographer’s dosemeter recorded a whole body dose of 3.1 mSv and the dose to his hands was estimated to be 90 mSv.
Where possible, having more than one team of radiographers working in the same location should be avoided. Where it cannot be avoided, it must be ensured that requests to initiate exposures are unambiguous. Mobile phones or two-way radios should be used as a means of communication between those who initiate exposures and those who set up the equipment and change films.
Methods of communication and signals used to indicate when exposures are starting and stopping should be agreed in advance and documented. A pre-warning signal should be used prior to commencement of any exposure; for x-ray sets this should operate automatically.