[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: 40CFR61.61]

[Page 50-52]
 
                   TITLE 40--PROTECTION OF ENVIRONMENT
 
         CHAPTER I--ENVIRONMENTAL PROTECTION AGENCY (CONTINUED)
 
PART 61_NATIONAL EMISSION STANDARDS FOR HAZARDOUS AIR POLLUTANTS
--Table of Contents
 
         Subpart F_National Emission Standard for Vinyl Chloride
 
Sec. 61.61  Definitions.

    Terms used in this subpart are defined in the Act, in subpart A of 
this part, or in this section as follows:
    (a) Ethylene dichloride plant includes any plant which produces 
ethylene dichloride by reaction of oxygen and hydrogen chloride with 
ethylene.
    (b) Vinyl chloride plant includes any plant which produces vinyl 
chloride by any process.
    (c) Polyvinyl chloride (PVC) plant includes any plant where vinyl 
chloride alone or in combination with other materials is polymerized.
    (d) Slip gauge means a gauge which has a probe that moves through 
the gas/liquid interface in a storage or transfer vessel and indicates 
the level of vinyl chloride in the vessel by the physical state of the 
material the gauge discharges.
    (e) Type of resin means the broad classification of resin referring 
to the basic manufacturing process for producing that resin, including, 
but not limited to, the suspension, dispersion, latex, bulk, and 
solution processes.
    (f) Grade of resin means the subdivision of resin classification 
which describes it as a unique resin, i.e., the most exact description 
of a resin with no further subdivision.
    (g) Dispersion resin means a resin manufactured in such a way as to 
form fluid dispersions when dispersed in a plasticizer or plasticizer/
diluent mixtures.
    (h) Latex resin means a resin which is produced by a polymerization 
process which initiates from free radical catalyst sites and is sold 
undried.
    (i) Bulk resin means a resin which is produced by a polymerization 
process in which no water is used.
    (j) Inprocess wastewater means any water which, during manufacturing 
or processing, comes into direct contact

[[Page 51]]

with vinyl chloride or polyvinyl chloride or results from the production 
or use of any raw material, intermediate product, finished product, by-
product, or waste product containing vinyl chloride or polyvinyl 
chloride but which has not been discharged to a wastewater treatment 
process or discharged untreated as wastewater. Gasholder seal water is 
not inprocess wastewater until it is removed from the gasholder.
    (k) Wastewater treatment process includes any process which modifies 
characteristics such as BOD, COD, TSS, and pH, usually for the purpose 
of meeting effluent guidelines and standards; it does not include any 
process the purpose of which is to remove vinyl chloride from water to 
meet requirements of this subpart.
    (l) In vinyl chloride service means that a piece of equipment either 
contains or contacts a liquid that is at least 10 percent vinyl chloride 
by weight or a gas that is at least 10 percent by volume vinyl chloride 
as determined according to the provisions of Sec. 61.67(h). The 
provisions of Sec. 61.67(h) also specify how to determine that a piece 
of equipment is not in vinyl chloride service. For the purposes of this 
subpart, this definition must be used in place of the definition of ``in 
VHAP service'' in subpart V of this part.
    (m) Standard operating procedure means a formal written procedure 
officially adopted by the plant owner or operator and available on a 
routine basis to those persons responsible for carrying out the 
procedure.
    (n) Run means the net period of time during which an emission sample 
is collected.
    (o) Ethylene dichloride purification includes any part of the 
process of ethylene dichloride purification following ethylene 
dichloride formation, but excludes crude, intermediate, and final 
ethylene dichloride storage tanks.
    (p) Vinyl chloride purification incudes any part of the process of 
vinyl chloride production which follows vinyl chloride formation.
    (q) Reactor includes any vessel in which vinyl chloride is partially 
or totally polymerized into polyvinyl chloride.
    (r) Reactor opening loss means the emissions of vinyl chloride 
occurring when a reactor is vented to the atmosphere for any purpose 
other than an emergency relief discharge as defined in Sec. 61.65(a).
    (s) Stripper includes any vessel in which residual vinyl chloride is 
removed from polyvinyl chloride resin, except bulk resin, in the slurry 
form by the use of heat and/or vacuum. In the case of bulk resin, 
stripper includes any vessel which is used to remove residual vinyl 
chloride from polyvinyl chloride resin immediately following the 
polymerization step in the plant process flow.
    (t) Standard temperature means a temperature of 20 [deg]C (69 
[deg]F).
    (u) Standard pressure means a pressure of 760 mm of Hg (29.92 in. of 
Hg).
    (v) Relief valve means each pressure relief device including 
pressure relief valves, rupture disks and other pressure relief systems 
used to protect process components from overpressure conditions. 
``Relief valve'' does not include polymerization shortstop systems, 
referigerated water systems or control valves or other devices used to 
control flow to an incinerator or other air pollution control device.
    (w) Leak means any of several events that indicate interruption of 
confinement of vinyl chloride within process equipment. Leaks include 
events regulated under subpart V of this part such as:
    (1) An instrument reading of 10,000 ppm or greater measured 
according to Method 21 (see appendix A of 40 CFR part 60);
    (2) A sensor detection of failure of a seal system, failure of a 
barrier fluid system, or both;
    (3) Detectable emissions as indicated by an instrument reading of 
greater than 500 ppm above background for equipment designated for no 
detectable emissions measured according to Method 21 (see appendix A of 
40 CFR part 60); and
    (4) In the case of pump seals regulated under Sec. 61.242-2, 
indications of liquid dripping constituting a leak under Sec. 61.242-2.

Leaks also include events regulated under Sec. 61.65(b)(8)(i) for 
detection of ambient concentrations in excess of background 
concentrations. A relief valve discharge is not a leak.

[[Page 52]]

    (x) Exhaust gas means any offgas (the constituents of which may 
consist of any fluids, either as a liquid and/or gas) discharged 
directly or ultimately to the atmosphere that was initially contained in 
or was in direct contact with the equipment for which gas limits are 
prescribed in Sec. Sec. 61.62(a) and (b); 61.63(a); 61.64 (a)(1), (b), 
(c), and (d); 61.65 (b)(1)(ii), (b)(2), (b)(3), (b)(5), (b)(6)(ii), 
(b)(7), and (b)(9)(ii); and 61.65(d). A leak as defined in paragraph (w) 
of this section is not an exhaust gas. Equipment which contains exhaust 
gas is subject to Sec. 61.65(b)(8), whether or not that equipment 
contains 10 percent by volume vinyl chloride.
    (y) Relief valve discharge means any nonleak discharge through a 
relief valve.
    (z) 3-hour period means any three consecutive 1-hour periods (each 
commencing on the hour), provided that the number of 3-hour periods 
during which the vinyl chloride concentration exceeds 10 ppm does not 
exceed the number of 1-hour periods during which the vinyl chloride 
concentration exceeds 10 ppm.

[41 FR 46564, Oct. 21, 1976, as amended at 42 FR 29006, June 7, 1977; 51 
FR 34908, Sept. 30, 1986; 55 FR 28348, July 10, 1990; 65 FR 62151, Oct. 
17, 2000]