Washington Committee for Occupational Safety and Health (WashCOSH) was founded in 1992 at a meeting of union and safety and health activists at the International Association of Machinists, Lodge 751 union hall. The goal was to improve workplace safety and health. Funding came from subcontracting on grants to the American Federation of State, County, and Municipal Employees and the Alice Hamilton Committee for Safety and Health from the National Institute for Environmental Health Sciences.

WashCOSH was involved in various projects over its history, including Ergonomics at a Buffalo Industries fabric recycling plant organized by Teamsters. The organization also offered a program of Painting Hazards Certification Training and other "painters' upgrade classes" for the Painters Advanced Training Institute at the Duwamish Branch of South Seattle Community College. Other trainings included Confined Space Entry Training and Hazardous Materials Emergency Response Training for the American Federation of State, County, and Municipal Employees. As well, the organization was involved with annual Workers' Memorial Day Events. WashCOSH published a quarterly newsletter, a guide called "Pollution Prevention for Construction Painting: A guide to help protect painters, the public and the environment" and organized an annual conferences including "Ergonomics, Safety, and Health in Construction, September 12-13, 1994" and "A Labor Union Response to Violence in the Workplace, June 10th, 1995"

WashCOSH created a multi-organizational governance committee, the WISHA Workplace Violence Committee. The executive board was made up of representatives from many unions, including Diane Zahn from the United Food and Commercial Workers (the first board president); Bill Anderson of the International Union of Painters and Allied Trades (Board President); Roger Yockey of United Food and Commercial Workers; and Jay Herzmark (Trustee, Board President) of AFSCME. Other unions represented on the board included International Brotherhood of Electrical Workers and the Office and Professional Employees International Union.

The first employee of WashCOSH was Anna Bachmann, who was hired as the Training Director in April 1993. She was later joined by Mark Catlin in the summer of 1993, who was the Director/Industrial Hygienist. Jay Herzmark replaced Catlin at the beginning of 1998. WashCOSH went out of business in the summer of 1998 because of tax issues.