Hazard exposure frequency: which level should you assess?

Safety standards and compliance

When assessing the frequency of hazard exposure do you instruct people to consider exposure at the corporate level, the site level, the crew level or the individual level? Each level would provide vastly different results, for example:

  1. Corporate exposure to employees working at heights could be several times per day, and
  2. Individual exposure to working at heights could be once per month.

I haven't thought of this until this morning, and upon reflection think it's rational for the assessment to taking into the account the assessors area of responsibility.