To be honest I think there were two seperate things there; the macho attitude to radiation exposure, and the mistake (understandably) made by a new team member.
The former is just a defence mechanism, probably related to them being in the forces where the alternative (expressing concern or fear) doesn't fit. But I don't think it would translate into "go on, lean out over there and you'll be top of the chart this month!!"
The former is just a defence mechanism, probably related to them being in the forces where the alternative (expressing concern or fear) doesn't fit. But I don't think it would translate into "go on, lean out over there and you'll be top of the chart this month!!"