Designations defined by NSF International (Ann Arbor, Michigan) for finished lubricants and components used in food-processing applications. H1 lubricants must be colorless, odorless, tasteless, non-toxic and meet other criteria; they are certified for incidental food contact. H2 lubricants may be used in food processing but only in situations where food contact cannot occur. H3, also known as soluble or edible oils, are used to clean and prevent rust on hooks, trolleys, and similar equipment. 3H lubricants are allowed to be in direct contact with food. HX1 ingredients must be used to formulate H1 lubricants.