40 CFR Part 63, Table 5

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Organic HAP/Chemical name (CAS No.)	Elastomer product/subcategory
BR	EPI \| EPR \| HYP \| NEO \| NBL \| NBR \| PBR/SBRS \| PSR \| SBL \| SBRE
Acrylonitrile (107131)	\| \| \| \| \| X \| X \| \| \| \|
1,3 Butadiene (106990)	\| \| \| \| \| X \| X \| X \| \| X \| X
Carbon Disulfide	\| \| \| \| \| X \| X \| X \| \| X \| X
Carbon Tetrachloride (56235)	\| \| \| X \| \| \| \| \| \| \|
Chlorobenzene (108907)	\| \| \| X \| \| \| \| \| \| \|
Chloroform (67663)	\| \| \| X \| \| \| \| \| \| \|
Chloroprene (126998)	\| \| \| \| X \| \| \| \| \| \|
Epichlorohydrin (106898)	\| X \| \| \| \| \| \| \| \| \|
Ethylbenzene (100414)	X \| \| \| \| \| \| \| \| \| X \|
Ethylene Dichloride (107062)	\| \| \| \| \| \| \| \| X \| \|
Ethylene Oxide (75218)	\| X \| \| \| \| \| \| \| X \| \|
Formaldehyde (50000)	\| X \| \| \| \| \| \| \| X \| \|
Hexane (110543)	X \| \| X \| \| \| \| \| X \| \| \|
Methanol (67561)	X \| \| \| \| \| \| \| X \| \| \|
Methyl Chloride (74873)	X \| \| \| X \| \| \| \| \| \| \|
Propylene Oxide (75569)	\| X \| \| \| \| \| \| \| \| \|
Styrene (100425)	\| \| \| \| \| \| \| X \| \| X \| X
Toluene (108883)	\| X \| X \| \| X \| \| \| X \| \| \|
Xylenes (1330207)	X \| \| \| \| \| \| \| \| \| \|
Xylene (m-) (108383)	X \| \| \| \| \| \| \| \| \| \|
Xylene (o-) (95476)	X \| \| \| \| \| \| \| \| \| \|
Xylene (p-) (106423)	X \| \| \| \| \| \| \| \| \| \|

CAS No. = Chemical Abstract Service Number.

BR = Butyl Rubber.

EPI = Epichlorohydrin Rubber.

EPR = Ethylene Propylene Rubber.

HYP = Hypalon TM.

NEO = Neoprene.

NBL = Nitrile Butadiene Latex.

NBR = Nitrile Butadiene Rubber.

PBR/SBRS = Polybutadiene and Styrene Butadiene Rubber by Solution.

PSR = Polysulfide Rubber.

SBL = Styrene Butadiene Latex.

SBRE = Styrene Butadiene Rubber by Emulsion.

[76 FR 22594, Apr. 21, 2011]