Milk production and sale in Washington is governed by the Washington Milk and Milk Products Act (Act), which is administered by the Department of Agriculture (WSDA) and sets out sanitary, animal health, and milk grading standards.  Under the Act, milk producers, distributers, and processors must be licensed by the WSDA. 

The 2017 Interstate Pasteurized Milk Ordinance (PMO) published by the United States Public Health Service, United States Department of Health and Human Services, and the United States Food and Drug Administration, is the national standard for milk sanitation. Adoption of the PMO by states is voluntary; however, complying with the PMO allows milk to move without restriction in interstate commerce.  The WSDA has adopted most of the provisions of the 2017 PMO through its rulemaking authority under the Act. 

The PMO establishes certain chemical, physical, bacteriological, and temperature standards for a variety of Grade "A" milk and milk products, including raw milk, pasteurized milk, ultra pasteurized milk, whey, and dry milk.  Exact standards vary between milk product type, however most Grade "A" milk products must test negative for any drugs, and not exceed 10 coliform per milliliter (ml).  Grade "A" pasteurized and ultra pasteurized milk and milk product bacterial limits may not exceed 20,000 per ml.  Grade "A" raw milk bacterial limits may not exceed 100,000 per ml prior to comingling with other producers' milk, and commingled milk may not exceed 300,000 per ml prior to pasteurization.  The somatic cell count for an individual producer's raw milk may not exceed 750,000 per ml.

Milk sold directly to the consumer from a small-scale farm is exempt from the requirements of the Washington Milk and Milk Products Act (Act) as long as the milk is not advertised for sale and the producer adheres to certain animal health and milk safety requirements.  A small-scale farm is defined as a location where there are no more than two producing dairy cows or nine producing small animals, such as sheep or goats. 

The animal health and milk safety requirements are as follows:

• All animals kept by the producer must be free of tuberculosis and brucellosis, as established by annual testing.
• Milk must be tested in at least four separate months during any six-month period using methods approved by Department of Agriculture.  Test results must show that milk does not contain:
  • any drugs;
  • more than 15,000 bacteria per milliliter (ml);
  • more than 25 coliform per ml; and
  • more than 500,000 somatic cells per ml for raw milk from a cow, or more than 750,000 somatic cells per ml for raw milk from a sheep or goat.

Whenever three of the last five consecutive tests exceeds any of the milk quality standards, the milk may not be sold until subsequent testing shows that milk again meets the standard.