(a) Visible warning devices shall be used when parked mobile
equipment creates a hazard to persons in other mobile equipment.
(b) Mobile equipment, other than forklifts, carrying loads that
project beyond the sides or more than four feet beyond the rear of the
equipment shall have a warning flag at the end of the projection. Under
conditions of limited visibility these loads shall have a warning light at
the end of the projection. Such flags or lights shall be attached to the end
of the projection or be carried by persons walking beside or behind the