You must meet the requirements …
in this section:
Prohibit tobacco smoke in your office work environment
This rule does not preempt any federal, state, municipal, or other local authority's regulation of indoor smoking that is more protective than this section.
Office work environment is an indoor or enclosed occupied space where clerical work, administration, or business is carried out. In addition, it includes:
• Other workplace spaces controlled by the employer and used by office workers, such as cafeterias, meeting rooms, and washrooms.
• Office areas of manufacturing and production facilities, not including process areas.
• Office areas of businesses such as food and beverage establishments, agricultural operations, construction, commercial trade, services, etc.
For work environments outside the office, contact your local health department using the link https://www.doh.wa.gov/YouandYourFamily/Tobacco/LawsRegulations or by calling them directly.