[Code of Federal Regulations]
[Title 49, Volume 4]
[Revised as of October 1, 2003]
From the U.S. Government Printing Office via GPO Access
[CITE: 49CFR234.213]

[Page 490]
 
                        TITLE 49--TRANSPORTATION
 
       CHAPTER II--FEDERAL RAILROAD ADMINISTRATION, DEPARTMENT OF 
                             TRANSPORTATION
 
PART 234--GRADE CROSSING SIGNAL SYSTEM SAFETY--Table of Contents
 
             Subpart D--Maintenance, Inspection, and Testing
 
Sec. 234.213  Grounds.

    Each circuit that affects the proper functioning of a highway-rail 
grade crossing warning system shall be kept free of any ground or 
combination of grounds that will permit a current flow of 75 percent or 
more of the release value of any relay or electromagnetic device in the 
circuit. This requirement does not apply to: circuits that include track 
rail; alternating current power distribution circuits that are grounded 
in the interest of safety; and common return wires of grounded common 
return single break circuits.