I recently noticed an employee cooking over a griddle and noticed they were wearing a visor. I've seen this quite frequently and it made me wonder if they are effective at keeping hair out of food. The alternatives I've seen are hats and hair nets, both of which intuitively seem better able to prevent hair contamination.
In looking at some guidelines, there's this statement from the Department of Food, Nutrition, and Packaging Science at Clemson University:
The U.S. Food Code (2005), which is the basis for the standards outlined in 2-4 and 2-5 of the NC School HACCP Plan, states that food employees shall wear hair restraints ... The NC Foodservice Rules specifically spells out what is effective hair restraint -- Effective hair restraints, such as hairnets, caps, or wrap around visors shall be worn by employees engaged in the preparation or handling of food to prevent the contamination of food or food contact surfaces.
My question is whether or not any studies have shown visors as similar in effectiveness compared to hats or, especially, hair nets. Given that there are regulations trying to prevent hair in food, one would think the regulations would require the best possible means.
I'm curious how visors made the list?