Posted By Des Daly
Rod,
I work in the scaffolding industry and we daily have upwards of 100 men working at high risk. However, as you rightly say the degree of risk can vary and controls measures can only be devised after a risk assessment and can therefore vary also. Our approach starts from the basic premise that our employees can never voluntarily accept risk. They may choose to work unsafe but that is much different from a tacit understanding between us, as the employer, and them, as the employee, that the risk is wholly theirs. We cannot delegate our general duty of care to our employees in both criminal and civil law.
In the scaffolding industry we think of the task to be carried out ( nature of the work, environment, rescue), the people who will do the work ( training, aptitude, attitude and experience, co-workers). The PPE required ( identified as the means to control the hazard through qualitative Risk Assessment) and any other factors that may impact on the work. It is not a simple exercise - I suggest that you may try to use the bottom upwards method i.e. Man has fallen, Why did he fall? What factors contributed to the accident etc. etc.- quite a useful way of analysing work processes.
Let me know if I can be of more help.

Des Daly