49 Cfr 325
49 CFR 325.doc
Motor Carrier Identification Report
49 CFR 325
OMB: 2126-0013
|
||||||
|
|
|
|
Home Page > Executive Branch > Code of Federal Regulations > Electronic Code of Federal Regulations Electronic Code of Federal Regulations (e-CFR)BETA TEST SITEe-CFR Data is current as of December 5, 2006 PART 325—COMPLIANCE WITH INTERSTATE MOTOR CARRIER NOISE EMISSION STANDARDS
Section Contents
Subpart B—Administrative Provisions
Subpart D—Measurement of Noise Emissions; Highway Operations
Subpart E—Measurement of Noise Emissions; Stationary Test
Subpart G—Exhaust Systems and Tires
Authority: 42 U.S.C. 4917; 49 U.S.C. 301; 49 CFR 1.73. Source: 40 FR 42437, Sept. 12, 1975, unless otherwise noted. Editorial Note: Nomenclature changes to part 325 appear at 66 FR 49869, Oct. 1, 2001. Subpart A—General Provisions§ 325.1 Scope of the rules in this part.(a) The rules in this part prescribe procedures for inspection, surveillance, and measurement of motor vehicles and motor vehicle equipment operated by motor carriers to determine whether those vehicles and that equipment conform to the Interstate Motor Carrier Noise Emission Standards of the Environmental Protection Agency, 40 CFR part 202. (b) Except as provided in paragraph (c) of this section, the rules in this part apply to motor carriers engaged in interstate commerce. The rules apply at any time or under any condition of highway grade, load, acceleration or deceleration. (c) The rules in this part do not apply to— (1) A motor vehicle that has a Gross Vehicle Weight Rating (GVWR) of 10,000 pounds (4,536 kg.) or less; (2) A combination of motor vehicles that has a Gross Combination Weight Rating (GCWR) of 10,000 pounds (4,536 kg.) or less; (3) The sound generated by a warning device, such as a horn or siren, installed in a motor vehicle, unless such device is intentionally sounded in order to preclude an otherwise valid noise emission measurement; (4) An emergency motor vehicle, such as a fire engine, an ambulance, a police van, or a rescue van, when it is responding to an emergency call; (5) A snow plow in operation; or (6) The sound generated by auxiliary equipment which is normally operated only when the motor vehicle on which it is installed is stopped or is operating at a speed of 5 miles per hour (8 kph) or less, unless such device is intentionally operated at speeds greater than 5 mph (8 kph) in order to preclude an otherwise valid noise measurement. Examples of that type of auxiliary equipment include, but are not limited to, cranes, asphalt, spreaders, ditch diggers, liquid or slurry pumps, auxiliary air compressors, welders, and trash compactors. § 325.3 Effective date.The rules in this part are effective on October 15, 1975. § 325.5 Definitions.(a) Statutory definitions. All terms defined in the Noise Control Act of 1972 (Pub. L. 92–574, 86 Stat. 1234) are used as they are defined in that Act. (b) Definitions in standards. All terms defined in §202.10 of the Interstate Motor Carrier Noise Emission Standards, 40 CFR 202.10, are used as they are defined in that section. (c) Additional definitions. (1) Hard test site means any test site having the ground surface covered with concrete, asphalt, packed dirt, gravel, or similar reflective material for more than 1/2 the distance between the microphone target point and the microphone location point. (2) Soft test site means any test site having the ground surface covered with grass, other ground cover, or similar absorptive material for 1/2 or more of the distance between the microphone target point and the microphone location point. (3) Ground cover means any of various low, dense-growing plants, such as ivy, myrtle, low weeds, or brush. (4) Traffic railing means any longitudinal highway traffic barrier system installed along the side or median of a highway. For the purpose of this part, a traffic railing must have at least 35 percent of its vertical height, from the ground surface to the top of the railing, open to free space in order to qualify as an acceptable object within a noise measurement test site. Further, for the purposes of this part, posts or other discrete supports shall be ignored when ascertaining open free space. (5) Relatively flat when used to describe a noise measurement site means a site which does not contain significant concave curvatures or slope reversals that may result in the focusing of sound waves toward the microphone location point. § 325.7 Allowable noise levels.Motor vehicle noise emissions, when measured according to the rules of this part, shall not exceed the values specified in Table 1. |
||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||||
.gif){kind=spacer}
.gif){kind=spacer}
.gif){kind=small}
Table 1_Maximum Permissible Sound Level Readings (Decibel (A)) \1,2\
----------------------------------------------------------------------------------------------------------------
Highway operation test Stationary tests
-------------------------------------------------------------------
Soft site Hard Site
--------------------------------------------
35 mi/h Above 35 35 mi/h Above 35 Soft site Hard site
or less mi/h or less mi/h
----------------------------------------------------------------------------------------------------------------
If the distance between the microphone
location point and the microphone target
point is_
31 ft ( 9.5m) or more but less than 35 87 91 89 93 89 91
ft (10.7m).............................
35 ft (10.7m) or more but less than 39 86 90 88 92 88 90
ft (11.9m).............................
39 ft (11.9m) or more but less than 43 85 89 87 91 87 89
ft (13.1m).............................
43 ft (13.1m) or more but less than 48 84 88 86 90 86 88
ft (14.6m).............................
48 ft (14.6m) or more but less than 58 83 87 85 89 85 87
ft (17.1m).............................
58 ft (17.1m) or more but less than 70 82 86 84 88 84 86
ft (21.3m).............................
70 ft (21.3m) or more but less than 83 81 85 83 87 83 85
ft (25.3m).............................
----------------------------------------------------------------------------------------------------------------
\1\ The speeds shown refer to measurements taken at sites having speed limits as indicated. These speed limits
do not necessarily have to be posted.
\2\ This table is based on motor carrier noise emission requirements specified in 40 CFR 202.20 and 40 CFR
202.21.
Table 2_Distance Correction Factors
------------------------------------------------------------------------
The value
dB(A) to
be applied
to the
If the distance between the microphone location point and observed
the microphone target point is sound
level
reading
is_
------------------------------------------------------------------------
31 feet (9.5 m) or more but less than 35 feet (10.7 m)...... -4
35 feet (10.7 m) or more but less than 39 feet (11.9 m)..... -3
39 feet (11.9 m) or more but less than 43 feet (13.1 m)..... -2
43 feet (13.1 m) or more but less than 48 feet (14.6 m)..... -1
48 feet (14.6 m) or more but less than 58 feet (17.7 m)..... 0
58 feet (17.7 m) or more but less than 70 feet (21.3 m)..... +1
70 feet (21.3 m) or more but less than 83 feet (25.3 m)..... +2
------------------------------------------------------------------------
[40 FR 42437, Sept. 12, 1975, as amended at 54 FR 50385, Dec. 6, 1989] § 325.75 Ground surface correction factors. 11 Table 1, in §325.7 is a tabulation of the maximum allowable sound level readings taking into account both the distance correction factors contained in §325.73 and the ground surface correction factors contained in §325.75. (a) Highway operations. When measurements are made in accordance with the rules in subpart D of this part upon a test site which is “hard,” a correction factor of 2 dB(A) shall be subtracted from the maximum observed sound level reading generated by the motor vehicle to determine whether the motor vehicle conforms to the Standards for Highway Operations, 40 CFR 202.20. (b) Stationary Test. When measurements are made in accordance with the rules in subpart E of this part upon a test site which is “soft,” a correction factor of 2 dB(A) shall be added to the numerical average of the recorded maximum observed sound level readings generated by the motor vehicle to determine whether the motor vehicle conforms to the Standard for Operation Under Stationary Test, 40 CFR 202.21. § 325.77 Computation of open site requirements—nonstandard sites.(a) If the distance between the microphone location point and the microphone target point is other than 50 feet (15.2 m), the test site must be an open site within a radius from both points which is equal to the distance between the microphone location point and the microphone target point. (b) Plan view diagrams of nonstandard test sites are shown in Figures 3 and 4. Figure 3 illustrates a test site which is larger than a standard test site and is based upon a 60-foot (18.3 m) distance between the microphone location point and the microphone target point. (See §325.79(b)(1) for an example of the application of the correction factor to a sound level reading obtained at such a site.) Figure 4 illustrates a test site which is smaller than a standard test site and is based upon a 35-foot (10.7 m) distance between the microphone location point and the microphone target point. (See §325.79(b)(2) for an example of the application of the correction factor to a sound level reading obtained at such a site.)
§ 325.79 Application of correction factors.(a) If two correction factors apply to a measurement they are applied cumulatively. (b) The following examples illustrate the application of correction factors to sound level measurement readings: (1) Example 1—Highway operations. Assume that a motor vehicle generates a maximum observed sound level reading of 86 dB(A) during a measurement in accordance with the rules in subpart D of this part. Assume also that the distance between the microphone location point and the microphone target point is 60 feet (18.3 m) and that the measurement area of the test site is acoustically “hard.” The corrected sound level generated by the motor vehicle would be 85 dB(A), calculated as follows: 86 dB(A) Uncorrected reading +1 dB(A) Distance correction factor −2 dB(A) Ground surface correction factor _____ 85 dB(A) Corrected reading (2) Example 2Stationary test. Assume that a motor vehicle generates maximum sound level readings which average 88 dB(A) during a measurement in accordance with the rules in subpart E of this part. Assume also that the distance between the microphone location point and the microphone target point is 35 feet (10.7 m), and that the measurement area of the test site is acoustically “soft.” The corrected sound level generated by the motor vehicle would be 87 dB(A), calculated as follows: 88 dB(A) Uncorrected average of readings −3 dB(A) Distance correction factor +2 dB(A) Ground surface correction factor _____ 87 dB(A) Corrected reading Subpart GExhaust Systems and Tires§ 325.91 Exhaust systems.A motor vehicle does not conform to the visual exhaust system inspection requirements, 40 CFR 202.22, of the Interstate Motor Carrier Noise Emission Standards, if inspection of the exhaust system of the motor vehicle discloses that the system— (a) Has a defect which adversely affects sound reduction, such as exhaust gas leaks or alteration or deterioration of muffler elements, (small traces of soot on flexible exhaust pipe sections shall not constitute a violation of this subpart); (b) Is not equipped with either a muffler or other noise dissipative device, such as a turbocharger (supercharger driven by exhaust gases); or (c) Is equipped with a cut-out, by-pass, or similar device, unless such device is designed as an exhaust gas driven cargo unloading system. § 325.93 Tires.(a) Except as provided in paragraph (b) of this section, a motor vehicle does not conform to the visual tire inspection requirements, 40 CFR 202.23, of the Interstate Motor Carrier Noise Emissions Standards, if inspection of any tire on which the vehicle is operating discloses that the tire has a tread pattern composed primarily of cavities in the tread (excluding sipes and local chunking) which are not vented by grooves to the tire shoulder or circumferentially to each other around the tire. (b) Paragraph (a) of this section does not apply to a motor vehicle operated on a tire having a tread pattern of the type specified in that paragraph, if the motor carrier who operates the motor vehicle demonstrates to the satisfaction of the Administrator or his/her designee that either— (1) The tire did not have that type of tread pattern when it was originally manufactured or newly remanufactured; or (2) The motor vehicle generates a maximum sound level reading of 90 dB(A) or less when measured at a standard test site for highway operations at a distance of 15.3 meters (50 feet) and under the following conditions: (i) The measurement must be made at a time and place and under conditions specified by the Administrator or his/her designee. (ii) The motor vehicle must be operated on the same tires that were installed on it when the inspection specified in paragraph (a) of this section occurred. (iii) The motor vehicle must be operated on a highway having a posted speed limit of more than 56.3 kph (35 mph). (iv) The sound level measurement must be made while the motor vehicle is operating at the posted speed limit. [40 FR 42437, Sept. 12, 1975, as amended at 60 FR 38743, July 28, 1995]
For
questions or comments regarding e-CFR editorial content, features,
or design, email ecfr@nara.gov. Last updated: August 7, 2006
|
| File Type | application/msword |
| File Title | Electronic Code of Federal Regulations: |
| Author | herman.dogan |
| Last Modified By | herman.dogan |
| File Modified | 2006-12-07 |
| File Created | 2006-12-07 |
© 2025 OMB.report | Privacy Policy