Which statement best describes the requirement for warning signs placement?

• A. Signs are optional in some areas
• B. Signs must be posted at all entrances to the work area where airborne asbestos may exceed ambient background levels
• C. Signs must be posted only outside the building
• D. Signs are required only during active work hours

Answer: (B)

Warning signs are required at all entrances to the work area where airborne asbestos may exceed ambient background levels. Placing signs at every entry point ensures anyone approaching or entering the area is immediately aware of the hazard before exposure could occur, so they can follow proper procedures, wear appropriate PPE, and restrict access as needed. The requirement is about informing and protecting people, not about optional measures or limited timing.

Signs should cover all access points, not just outside the building or only during active work hours, because hazards can exist at different times and in various entry points. This is why the rule emphasizes placement at every entrance to the work zone where asbestos air levels could be elevated.