[chris vickery]

Lynn and others;
The trend here in Canada now for most industrial sites is to wear FR/AF coveralls (fire retardant and/or arc flash)
This goes for anyone working on site, and is especially true for all workers in utilities (electrical, gas etc) as well as others in mining, petro chemical etc.
This is a broad brushed effort to help ensure all workers safety, it is not neccessarily trade specific. The truck drivers wear them, mechanics, crane operators, electricians- everyone. Cleanliness is important as well to keep the material free of greases, oils, chemicals etc.
Sure, a person may ask "why does a crane operator require them?"
You never know, as any added layer of personal protection is better than not.