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e-CFR data is current as of February 22, 2021

Title 49 → Subtitle B → Chapter III → Subchapter A → Part 325

TITLE 49—Transportation

Subtitle B—OTHER REGULATIONS RELATING TO TRANSPORTATION (CONTINUED)

CHAPTER III—FEDERAL MOTOR CARRIER SAFETY ADMINISTRATION, DEPARTMENT OF TRANSPORTATION

SUBCHAPTER A—GENERAL REGULATIONS

PART 325—COMPLIANCE WITH INTERSTATE MOTOR CARRIER NOISE EMISSION STANDARDS

rule

Subpart A—GENERAL PROVISIONS

§325.1
Scope of the rules in this part.
§325.3
[Reserved]
§325.5
Definitions.
§325.7
Allowable noise levels.
§325.9
Measurement tolerances.
rule

Subpart B—ADMINISTRATIVE PROVISIONS

§325.11
Issuance, amendment, and revocation of the rules in this part.
§325.13
Inspection and examination of motor vehicles.
rule

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.
rule

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.
rule

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.
rule

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—nonstandard sites.
§325.79
Application of correction factors.
rule

Subpart G—EXHAUST SYSTEMS AND TIRES

§325.91
Exhaust systems.
§325.93
Tires.

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