[Code of Federal Regulations]
[Title 40, Volume 8]
[Revised as of July 1, 2007]
From the U.S. Government Printing Office via GPO Access
[CITE: 40CFR61.242-4]

[Page 159-160]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 61_NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS
--Table of Contents
 
   Subpart V_National Emission Standard for Equipment Leaks (Fugitive 
                            Emission Sources)
 
Sec. 61.242-4  Standards: Pressure relief devices in gas/vapor service.

    (a) Except during pressure releases, each pressure relief device in 
gas/vapor service shall be operated with no detectable emissions, as 
indicated by an instrument reading of less than 500

[[Page 160]]

ppm above background, as measured by the method specified in Sec. 
61.245(c).
    (b)(1) After each pressure release, the pressure relief device shall 
be returned to a condition of no detectable emissions, as indicated by 
an instrument reading of less than 500 ppm above background, as soon as 
practicable, but no later than 5 calendar days after each pressure 
release, except as provided in Sec. 61.242-10.
    (2) No later than 5 calendar days after the pressure release, the 
pressure relief device shall be monitored to confirm the condition of no 
detectable emissions, as indicated by an instrument reading of less than 
500 ppm above background, as measured by the method specified in Sec. 
61.245(c).
    (c) Any pressure relief device that is routed to a process or fuel 
gas system or equipped with a closed-vent system capable of capturing 
and transporting leakage from the pressure relief device to a control 
device as described in Sec. 61.242-11 is exempt from the requirements 
of paragraphs (a) and (b) of this section.
    (d)(1) Any pressure relief device that is equipped with a rupture 
disk upstream of the pressure relief device is exempt from the 
requirements of paragraphs (a) and (b) of this section, provided the 
owner or operator complies with the requirements in paragraph (d)(2) of 
this section.
    (2) After each pressure release, a new rupture disk shall be 
installed upstream of the pressure relief device as soon as practicable, 
but no later than 5 calendar days after each pressure release, except as 
provided in Sec. 61.242-10.

[49 FR 23513, June 6, 1984; 49 FR 38946, Oct. 2, 1984, as amended at 65 
FR 78281, Dec. 14, 2000]