3.2.5 Prohibited materials. Asbestos materials shall not be used in any form in any part
of the vehicle. No item, part or assembly shall contain radioactive materials in which the
specific activity is greater than 0.002 microcurie per gram or activity per item equals or exceeds
3.3 Performance. The fully equipped semitrailer shall evidence no part failure or
permanent set or interference between parts when towed at speeds as great as: 25 miles per hour
(mph), with rated payload, over unimproved roads and other reasonably hard, uneven terrain;
40 mph with rated payload over highways; and 55 mph without payload over highways.
3.3.1 Turning ability. The semitrailer shall be capable of assuming a 90 degree angle to
the coupled towing vehicle without cramping or damage to the semitrailer or the towing vehicle.
3.3.2 Brake performance. The service brakes shall stop the semitrailer tractor
combination, with the semitrailer loaded with specified payload, within the stopping distance
requirements of Federal Motor Carrier Safety Regulation 393.52. Requirements shall be met
with a truck tractor loaded to its full rated gross vehicle weight (GVW) and gross combination
3.3.3 Tracking ability. The semitrailer shall conform to the tracking ability requirements
of Federal Motor Carrier Safety Regulation 393.70(a).
3.3.4 Loading capability. The semitrailer shall be capable of being loaded from the rear
with a mobile load equal to the required payload capacity without part failure, deformation,
permanent set, or interference in any part of the semitrailer.
3.4 Payload and distribution. The rated payload capacity shall be not less than
30,000 pounds for size 15 semitrailers, 40,000 pounds for size 20 semitrailers, 44,000 pounds for
size 22 semitrailers, 50,000 pounds for size 25 semitrailers, and 60,000 pounds for size 30
3.4.1 Weight distribution. Except for size 30, load bearing members shall be rated for
the loads imposed with the rated payload evenly distributed between the rear of the gooseneck
and the center line of the rear bogie. For size 30, load bearing members shall be rated for the
loads imposed with the rated payload evenly distributed for not less than 12 feet rearward from
the rear of the gooseneck.
3.5 Dimensions and clearances. The semitrailer, without payload, uncoupled from the
towing vehicle, resting on its landing legs, on level ground, and with the platform level, shall
conform to the dimensions specified in table I.