540 CMR 4.10
Special Safety Requirements for Commonwealth Heavy Vehicles and Contractor Heavy Vehicles.
(1) Unless a vehicle is exempt pursuant to 540 CMR 4.10(7), or a waiver has been issued
pursuant to 540 CMR 4.12, a registered Commonwealth Heavy Vehicle or Contractor Heavy
Vehicle shall be equipped with Lateral Protective Devices, Convex Mirrors, Cross Over Mirrors,
and Back Up Cameras.
(2) Aftermarket Modifications and accessories including bug deflectors, chrome visors, and
bull bars that reduce the ability of the vehicle operator to directly see Vulnerable Users in the
vicinity of the vehicle or that increase fatality and serious injury risk to Vulnerable Users in a
collision with the vehicle are prohibited.
(3) Lateral Protective Devices. In accordance with US Department of Transportation Volpe
Side Guard Standard DOT-VNTSC-OSTR-16-05, as amended, lateral protective devices or side
guards on vehicles that are subject to the provisions of 540 CMR 4.10(3) shall be installed,
throughout their length, to offer effective protection to vulnerable users against the risk of falling
under the sides of the vehicle and being caught under the wheels. Lateral Protective Devices
shall meet the following requirements:
(a) Allow for a maximum 13.8 inch ground clearance;
(b) Allow for a maximum 13.8 inch top clearance;
(c) Allow for a maximum horizontal distance between the front tire (cabover trucks) and
the lateral protective device of 11.8 inches, however, if the front tire is located next to a step
or tank, the maximum horizontal distance from the front tire to the lateral protective device
shall be 3.9 inches, and if the front tire is located next to landing gear (semi-trailer), the
maximum horizontal distance from the front tire to the lateral protective device shall be 9.8";
(d) Be recessed a maximum of 1.2 inches from the face of the front and rear tires;
(e) Have a minimum impact strength of 450 pounds applied perpendicularly to any part of
its surface by the center of a ram the face of which is circular and not more than 8.7 inches
in diameter;
(f) Be capable of withstanding 450 pounds of force applied perpendicularly to any part of
its surface by the center of a flat, circular plate of diameter not greater than 8.7 inches, such
that the deflection of the loaded side guard measured at the center of the plate does not
exceed (1) 5.9 inches anywhere, or (2) 1.2 inches in the rearmost 9.8 inches. A manufacturer
may demonstrate compliance using a valid engineering calculation, such as finite element
analysis;
(g) Achieve a smooth and continuous longitudinal impact surface flush with the vehicle or
tire sidewall, whichever creates the outermost plane of the vehicle, and shall not be
susceptible to loosening due to vibration in the normal use of the vehicle;
(h) May include rail type guards, provided that such rails shall not be less than four inches
tall and not more than 11.8 inches apart; and
(i) Acceptable lateral protective device protection as an alternative means of compliance can
be provided by any combination of vehicle body, fuel tanks, tag axles, tool boxes, or
purpose-built side guards comprising a smooth surface flush with the vehicle sidewall, and
meeting all of the dimensional and strength specifications set forth above.