2010 Pennsylvania Code
Title 75 - VEHICLES
Chapter 43 - Lighting Equipment
4305 - Vehicular hazard signal lamps.

     § 4305.  Vehicular hazard signal lamps.
        (a)  General rule.--Simultaneous flashing of the two front
     and two rear signal lamps shall indicate a vehicular traffic
     hazard. The driver of a motor vehicle equipped with simultaneous
     flashing signals shall use the signals when the vehicle is
     stopped or disabled on a highway, except when the vehicle is
     stopped in compliance with a traffic-control device or when
     legally parked. Drivers of other vehicles shall exercise
     extraordinary care in approaching, overtaking and passing a
     vehicle displaying vehicular hazard warning signals.
        (b)  Use outside business and residence districts.--Outside
     of a business or residence district:
            (1)  The driver of a motor vehicle or combination
        equipped with simultaneous flashing signals shall use the
        signals when the vehicle is unable to maintain a speed of at
        least 25 miles per hour because of weather, grade or other
        similar factors or is unable to maintain a speed consistent
        with the normal flow of traffic.
            (2)  The driver of a bus equipped with simultaneous
        flashing signals shall use the signals when the bus is
        stopped with one or more wheels on the roadway between dusk
        and dawn for the purpose of receiving or discharging
        passengers.
        (c)  Use below minimum speed limit.--The driver of a motor
     vehicle or combination equipped with simultaneous flashing
     signals shall use the signals when the vehicle is not
     maintaining at least the minimum speed established in accordance
     with the provisions of section 3364 (relating to minimum speed
     regulation).
     (June 25, 1987, P.L.30, No.13, eff. 60 days)