3A Sanitary & E3A O-ring & Seal Materials:
3-A Sanitary Standards have been formulated by the United States Public Health Service, the International Association of Milk Food and Environmental Standards, and the Dairy and Food Industries Supply Association. A similar document, E-3A Sanitary Standards, was later formulated by this same group plus the United States Department of Agriculture and the Institute of American Poultry Industries.
The 3-A standards are intended for elastomers to be used as product contact surfaces in dairy equipment.
E-3A standards are intended for elastomers used as product contact surfaces in egg processing equipment.
The requirements of the two specifications are essentially identical, the intent in each case being to determine whether rubber materials are capable of being cleaned and receiving an effective bactericidal treatment while still maintaining their physical properties after repeated applications of the cleaning process chemicals.