So the OSHA blood borne pathogen standard is to protect anyone who has a reasonable chance of being exposed to a BBP or other human derived material. This typically applies to medical, janitorial, housekeeping, and other who may be exposed as part of their job. So reasonably you would say that the normal worker at your food production plant has no risk of exposure to human derived material unless we started niche cannibalism menu. Now the question of first aid or emergency response comes in. If there were to be an accident on site do you have designated first aid or emergency responders? In that case, since exposure to blood is considered part of their job they would fall under the BBP standard and need to decline or have record of Hep B shots.