Physical hazard means an existing or potential hazard that can cause death or serious physical damage. Examples include but are not limited to: explosives (as defined by Section 5237, the definition of “explosive”); mechanical, electrical, hydraulic and pneumatic energy; radiation; temperature extremes; engulfment; noise; and inwardly converging surfaces. Physical hazard also includes chemicals that can cause death or serious physical damage through the skin or eye contact (rather than through inhalation).