[Code of Federal Regulations]

[Title 40, Volume 24]

[Revised as of July 1, 2006]

From the U.S. Government Printing Office via GPO Access

[CITE: 40CFR201.23]



[Page 76]

 

                   TITLE 40--PROTECTION OF ENVIRONMENT

 

         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)

 

PART 201_NOISE EMISSION STANDARDS FOR TRANSPORTATION EQUIPMENT; INTERSTATE 

RAIL CARRIERS--Table of Contents

 

                     Subpart C_Measurement Criteria

 

Sec.  201.23  Test site, weather conditions and background noise criteria 

for measurement at a 30 meter (100 feet) distance of the noise from 

locomotive and rail car operations and locomotive load cell test stands.



    (a) The standard test site shall be such that the locomotive or 

train radiates sound into a free field over the ground plane. This 

condition may be considered fulfilled if the test site consists of an 

open space free of large, sound reflecting objects, such as barriers, 

hills, signboards, parked vehicles, locomotives or rail cars on adjacent 

tracks, bridges or buildings within the boundaries described by Figure 

1, as well as conforms to the other requirements of this Sec.  201.23.

    (b) Within the complete test site, the top of at least one rail upon 

which the locomotive or train is located shall be visible (line of 

sight) from a position 1.2 meters (4 feet) above the ground at the 

microphone location, except as provided in paragraph (c) of this 

section.

    (c) Ground cover such as vegetation, fenceposts, small trees, 

telephone poles, etc., shall be limited within the area in the test site 

between the vehicle under test and the measuring microphone such that 80 

percent of the top of at least one rail along the entire test section of 

track be visible from a position 1.2 meters (4 feet) above the ground at 

the microphone location; except that no single obstruction shall account 

for more than 5 percent of the total allowable obstruction.

    (d) The ground elevation at the microphone location shall be within 

plus 1.5 meters (5 feet) or minus 3.0 meters (10 feet) of the elevation 

of the top of the rail at the location in-line with the microphone.

    (e) Within the test site, the track shall exhibit less than a 2 

degree curve or a radius of curvature greater than 873 meters (2,865 

feet). This paragraph shall not apply during a stationary test. The 

track shall be tie and ballast, free of special track work and bridges 

or trestles.

    (f) Measurements shall not be made during precipitation.

    (g) The maximum A-weighted fast response sound level observed at the 

test site immediately before and after the test shall be at least 10 

dB(A) below the level measured during the test. For the locomotive and 

rail car pass-by tests this requirement applies before and after the 

train containing the rolling stock to be tested has passed. This 

background sound level measurement shall include the contribution from 

the operation of the load cell, if any, including load cell contribution 

during test.

    (h) Noise measurements may only be made if the measured wind 

velocity is 19.3 km/hr (12 mph) or less. Gust wind measurements of up to 

33.2 km/hr (20 mph) are allowed.