If you're in occupational safety, occupational health, management, labor, or just a member of the general public, you can nominate yourself for OSHA's National Advisory Committee on Occupational Safety and Health (NACOSH).
The 12-member NACOSH advises the Secretaries of Labor and Health and Human Services on matters relating to the administration of the Occupational Safety and Health Act of 1970 -- the act that brought both OSHA and NACOSH into existence.