[Code of Federal Regulations]
[Title 46, Volume 2]
[Revised as of October 1, 2004]
From the U.S. Government Printing Office via GPO Access
[CITE: 46CFR63.20-1]

[Page 314-315]
 
                           TITLE 46--SHIPPING
 
   CHAPTER I--COAST GUARD, DEPARTMENT OF HOMELAND SECURITY (CONTINUED)
 
PART 63_AUTOMATIC AUXILIARY BOILERS--Table of Contents
 
          Subpart 63.20_Additional Control System Requirements
 
Sec. 63.20-1  Specific control system requirements.


    In addition to the requirements found in ANSI/ASME CSD-1/CSD-1a, the 
following requirements apply for specific control systems:
    (a) Primary safety control system. Following emergency safety trip 
control operation, the air flow to the boiler must not automatically 
increase. For this condition, postpurge must be accomplished manually.
    (b) Combustion control system. A low fire interlock must ensure low 
fire start when variable firing rates are used.
    (c) Water level controls and low water cutoff controls. Water level 
controls must be constructed and located to minimize the effects of 
vessel roll and pitch. Float chamber low water cutoff controls using 
stuffing boxes to transmit the motion of the float from the chamber to 
the external switches are prohibited. No outlet connection other than 
pressure controls, water columns,

[[Page 315]]

drains, and steam gages may be installed on the float chamber or on the 
pipes connecting the float chamber to the boiler. The water inlet valve 
must not feed water into the boiler through the float chamber. The 
boiler feed piping must comply with the applicable requirements of Sec. 
56.50-30 of this chapter.