An excellent short article from Adrian Meiedema of Denton’s.  A key take-away:  “if the injury resulted from a hazard to which workers were also exposed, the OHSA applies and the employer may be charged and fined”.

In our world of small and medium sized enterprises [SMEs] we are often too casual about letting non-employees into areas which may be a danger.  We are often too sure of everybody’s constantly functioning attention and common sense.   No-one, however, is always paying attention, and no-one always uses their common sense (and some forget to turn it on), and not every person has the intimate knowledge of danger spots in work areas that owners and workers don’t even think about any more.   Keep work areas safe and within OHSA requirements, and keep visitors out of those work areas.