[Code of Federal Regulations]
[Title 49, Volume 2]
[Revised as of October 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR179.100-12]

[Page 1071-1072]
 
                        TITLE 49--TRANSPORTATION
 
   CHAPTER I--PIPELINE AND HAZARDOUS MATERIALS SAFETY ADMINISTRATION, 
                      DEPARTMENT OF TRANSPORTATION
 
PART 179_SPECIFICATIONS FOR TANK CARS--Table of Contents
 
 Subpart C_Specifications for Pressure Tank Car Tanks (Classes DOT-105, 
                         109, 112, 114 and 120)
 
Sec.  179.100-12  Manway nozzle, cover and protective housing.

    (a) Manway nozzles must be of approved design of forged or rolled 
steel for steel tanks or of fabricated aluminum alloy for aluminum 
tanks, with an access opening of at least 18 inches inside diameter, or 
at least 14 inches by 18 inches around or oval. Each nozzle must be 
welded to the tank and the opening reinforced in an approved manner in 
compliance with the requirements of AAR Specifications for Tank Cars, 
appendix E, Figure E10 (IBR, see Sec.  171.7 of this subchapter).
    (b) Manway cover shall be machined to approved dimensions and be of 
forged or rolled carbon or alloy steel, rolled aluminum alloy or nickel 
when required by the lading. Minimum thickness is listed in Sec.  
179.101. Manway cover shall be attached to manway nozzle by through or 
stud bolts not entering tank, except as provided in Sec.  179.103-2(a).
    (c) Except as provided in Sec.  179.103, protective housing of cast, 
forged or fabricated approved materials must be bolted to manway cover 
with not less

[[Page 1072]]

than twenty \3/4\-inch studs. The shearing value of the bolts attaching 
protective housing to manway cover must not exceed 70 percent of the 
shearing value of bolts attaching manway cover to manway nozzle. Housing 
must have steel sidewalls not less than three-fourths inch in thickness 
and must be equipped with a metal cover not less than one-fourth inch in 
thickness that can be securely closed. Housing cover must have suitable 
stop to prevent cover striking loading and unloading connections and be 
hinged on one side only with approved riveted pin or rod with nuts and 
cotters. Openings in wall of housing must be equipped with screw plugs 
or other closures.

[29 FR 18995, Dec. 29, 1964. Redesignated at 32 FR 5606, Apr. 5, 1967, 
and amended by Amdt. 179-10, 36 FR 21345, Nov. 6, 1971; 68 FR 75760, 
Dec. 31, 2003]