l-square-foot area at any one time without damage or permanent deformation. The fenders shall
be constructed of lightweight fiber glass reinforced plastic or aluminum material. The top
surface of the fenders shall be treated with an antiskid surface. The outer edges of the fenders
shall be rolled to reduce side road splash. The splash guards shall be of a size not less than
12 by 18 inches, and shall include antisail characteristics. The guards shall be of fiber glass
reinforced polyester or of solid polyvinyl chloride homopolymers and monomeric low
temperature plasticisers without reinforcement.
3.4.8 Rear bumper. The distributor shall be equipped with a horizontal rear bumper,
extending the full width of the distributor. The bumper shall be not less than 8 inches vertical
height and shall extend rearward not less than 2 inches from any part of the distributor. The left
and right ends of the bumper shall be rounded and closed to prevent hooking when sideswiped
by an obstruction.
3.4.9 Intervehicular connections. The distributor shall be furnished with an intervehicular
electrical harness and two airbrake lines for connecting the truck's electrical and airbrake
systems to the distributor systems. All intervehicular connections shall be installed on the
distributor so that they extend forward between 36 and 42 inches toward the towing vehicle, and
rearward at least 20 inches on the towbar, measured from the center of the towbar eye. A spring
clip shall be installed to hold the electrical harness plug to the towbar with the harness doubled
back on the distributor. Two dummy couplings shall be installed to hold the airbrake line ends
with the lines doubled back. Each dummy coupling shall be mounted perpendicular to the
mounting surface and clearance shall be provided for the spring dust cover on the coupling.
Intervehicular connections, when connected and when stowed, shall be routed or protected so
that dropping of the tailgate of the towing vehicle shall not cause physical damage.
3.4.10 Towbar components. A towbar eye conforming to SAE J847 shall be furnished and
installed on the towbar within 1/8-inch tolerance of the longitudinal centerline of the distributor.
The towbar shall be within the height range specified in table I. The lunette (towbar eye) shall
be inserted in a support that is welded into the towbar. The lunette support shall prevent lunette
rotation. Two safety chains, equipped with safety type grabhooks, shall be furnished and shall
conform to SAE J697 and to the DOT Motor Carrier Safety Regulations. The forward length of
each chain hook shall be between 36 and 42 inches measured from the center of the towbar eye.
The safety chain hook shall pass through the shackles of the towing vehicle specified in 3.1.2.
The attachment end of the safety chains shall be either perimeter welded or bolted to the towbar.
The towbar shall be of the A-frame type. The towbar shall be constructed to embody structural
strength to meet or exceed the following requirements: support and transport the weight of the
distributor at the GVW specified in table I; transmit and distribute the imposed load to the
suspension system and eye, and resist bending and twisting without permanent deformation or
part failure when subjected to the performance requirements specified herein.