Part 325: Compliance with Interstate Motor Carrier Noise Emission Standards

Part	Regulation	Guidance
Subpart A - General Provisions
325.1	Scope of the rules in this part	Yes
325.3	Effective date
325.5	Definitions
325.7	Allowable noise levels
325.9	Measurement tolerances
Subpart B - Administrative Provisions
325.11	Issuance, amendment, and revocation of the rules in this part
325.13	Inspection and examination of motor vehicles
Subpart C - Instrumentation
325.21	Scope of the rules in this subpart
325.23	Type of measurement systems which may be used
325.25	Calibration of measurement systems
325.27	Use of a windscreen
Subpart D - Measurement of Noise Emissions; Highway Operations
325.31	Scope of the rules in this subpart
325.33	Site characteristics; highway operations
325.35	Ambient conditions; highway operations
325.37	Location and operation of sound level measurement system; highway operations
325.39	Measurement procedure; highway operations
Subpart E - Measurement of Noise Emissions; Stationary Test
325.51	Scope of the rules in this subpart
325.53	Site characteristics; stationary test.
325.55	Ambient conditions; stationary test
325.57	Location and operation of sound level measurement systems; stationary test
325.59	Measurement procedure; stationary test
Subpart F - Correction Factors
325.71	Scope of the rules in this subpart
325.73	Microphone distance correction factors.
325.75	Ground surface correction factors
325.77	Computation of open site requirements non standard sites
325.79	Application of correction factors
325.91 - .93	Subpart G - Exhaust Systems and Tires
325.91	Exhaust systems
325.93	Tires