OSHA uses statistics to determine where their efforts should be focused.  If there are more accidents and resulting injuries in a given industry, OSHA focuses its investigations on that particular industry.  However, officials are beginning to find that certain businesses in certain industries have been underreporting accidents and injuries.  http://www.fairwarning.org/2010/11/targeting-bogus-injury-records-osha-takes-heat-from-all-sides/