The Wiring System requirements of 393.28 are not specific as to what constitutes a violation of the section.

393.28 states "Electrical wiring shall be installed and maintained to conform to SAE-J1292". Most inspectors do not have access to J1292 and the requirements of this standard are not clear on what constitutes a violation of the CMV wiring system.

Previous discussion with FMCSA is that a violation does not exist until the wiring insulation is damaged and wiring is exposed. Add violation Guidance to CVSA Operational Policy 15 that a violation of 393.28 exists when the protective insulation is damaged to the extent that wiring/wires are exposed.

It was discussed that students in Part B class are taught that a violation does not exist until insulation is damaged and wiring is exposed but there is no written guidance anywhere. In previous discussions with FMCSA, it was stated that if the wiring insulation is damaged and wiring is exposed, then it is a violation.

There was a question on if it’s a ground wire, should it be documented as a violation in this scenario? There was discussion about hot wires and ground wires and either could potentially lead to problems with the lighting if bare wire is exposed. There was a question about burned and fused wire, but not exposed, should that be included in the guidance as a violation. Comment that it would be included with the light not working and that a separate violation would not be needed.

The consensus of the committee is that the current FMCSA guidance and the material taught to Part B students should be used and documented in Operational Policy 15 for reference. A motion to add regulatory guidance to the Miscellaneous section of Operational Policy 15, that a violation of wiring should be documented when bare wire is exposed.

XX. MISCELLANEOUS

b.(5) When should a violation of the wiring system be documented?

Answer: A violation of the wiring system should be documented when the wiring insulation is damaged to the extent that bare wire is exposed.