§325.1 Scope of the rules in this part.

Question 1: What noise emission requirements are applicable to auxiliary generators?

Guidance: Auxiliary generators which normally operate only when a Commercial Motor Vehicle (CMV) is stopped or moving at 5 mph or less are ‘‘auxiliary equipment’’ of the kind contemplated by U.S. Environmental Protection Agency and are, therefore, exempt from the noise limits in Part 325. However, noise from generators that run while the CMV is moving at higher speeds would be measured as part of total vehicle noise.

Question 2: Do refrigeration units on tractor-trailer combinations fall within the exemption listed in part 325, subpart A of the Federal Motor Carrier Safety Regulations?

Guidance: No.