[Code of Federal Regulations]
[Title 49, Volume 4]
[Revised as of October 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR229.49]

[Page 431]
 
                        TITLE 49--TRANSPORTATION
 
       CHAPTER II--FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF 
                             TRANSPORTATION
 
PART 229_RAILROAD LOCOMOTIVE SAFETY STANDARDS--Table of Contents
 
                      Subpart C_Safety Requirements
 
Sec.  229.49  Main reservoir system.

    (a)(1) The main reservoir system of each locomotive shall be 
equipped with at least one safety valve that shall prevent an 
accumulation of pressure of more than 15 pounds per square inch above 
the maximum working air pressure fixed by the chief mechanical officer 
of the carrier operating the locomotive.
    (2) Except for non-equipped MU locomotives built prior to January 1, 
1981, each locomotive that has a pneumatically actuated system of power 
controls shall be equipped with a separate reservoir of air under 
pressure to be used for operating those power controls. The reservoir 
shall be provided with means to automatically prevent the loss of 
pressure in the event of a failure of main air pressure, have storage 
capacity for not less than three complete operating cycles of control 
equipment and be located where it is not exposed to damage.
    (b) A governor shall be provided that stops and starts or unloads 
and loads the air compressor within 5 pounds per square inch above or 
below the maximum working air pressure fixed by the carrier.
    (c) Each compressor governor used in connection with the automatic 
air brake system shall be adjusted so that the compressor will start 
when the main reservoir pressure is not less than 15 pounds per square 
inch above the maximum brake pipe pressure fixed by the carrier and will 
not stop the compressor until the reservoir pressure has increased at 
least 10 pounds.