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PROPANE†

Chemical Identification
CAS #	74-98-6
Formula	C₃H₈
Synonyms	bottled gas; dimethyl methane; n-propane; propyl hydride; LPG

Physical Properties
Physical description	Colorless, odorless gas.
Boiling point	-44°F	Molecular weight	44.1
Freezing point/melting point	-306°F	Vapor pressure	8.4 atm at 70°F
Flash point	-156°F	Vapor density	1.55
Specific gravity	0.59 at -58°F	Ionization potential	11.07 eV
Lower explosive limit (LEL)	2.1%	Upper explosive limit (UEL)	9.5%
NFPA health rating	2	NFPA fire rating	4
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	2150
Sampling group
Sampler/Sampling media	2 tubes, ORBO™ 91 Carbosieve® S-III (130/65) in series [Supelco 20360]
Sampling time^*	50 min
Sampling volume (TWA)^*	5 L
Sampling flow rate (TWA)^*	0.1 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-FID
Method reference	OSHA PV2077 (partially validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Detector tube	Detector tube	Combustible gas meter	CMS Chip
Model/Type	Dräger - Hydrocarbons 0.1%/b, CH26101	Gastec 103	Matheson-Kitagawa 8014-125SA		Propane, 100-2000 ppm range
Sampling information (see manufacturer instructions)	7-15 strokes, approx 0.5 vol-%-1.3 vol-% range, uncertainty 49%	0.5-2 strokes, 0.05-2.4% range, uncertainty 16%	follow mfr instructions, approx 0.02-0.5% range	NIOSH Manual of Analytic Methods (NIOSH S87), fully validated

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	1000 ppm (1800 mg/m³)	REL-TWA	1000 ppm (1800 mg/m³)	TLV-TWA	Withdrawn [2013]	PEL-TWA	1000 ppm (1800 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	N	Skin notation	N
Notes: See 29 CFR 1910.1000 Table Z-1. Propane is classified as a simple asphyxiant and exposure is also addressed in OSHA Construction and Maritime standards. For OSHA's construction regulations, see 29 CFR 1926.55 Table 1: [E] The limiting factor is the available oxygen which shall be at least 19.5% and be within the requirements addressing explosion in 29 CFR 1926. For OSHA's maritime regulations, see 29 CFR 1915.1000 Table Z-Shipyards: [E] The limiting factor is the available oxygen which shall be at least 18% and be within the requirements addressing explosion in 29 CFR 1915, Subpart B.		Notes:		Notes: See Appendix F: Minimal Oxygen Content. Propane is listed as a simple asphyxiant and explosion hazard.		Notes: A number of gases and vapors, when present in high concentrations, act primarily as asphyxiants without other adverse effects. A concentration limit is not included for each material because the limiting factor is the available oxygen. (Several of these materials present fire or explosion hazards.)
Health factors: See NIH-NLM PubChem.		IDLH	2100 ppm
Carcinogenic classifications: Not listed		Notes: 10% LEL
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Propane

NIOSH: Pocket Guide to Chemical Hazards - Propane

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Propane. See annual publication for most recent information.
Fonseca, C.A., Auerbach, D.S. and Suarez, R.V.: The forensic investigation of propane gas asphyxiation. Am. J. Forensic Med. Pathol. 23(2): 167-169, 2002.

Last Updated Date : 01/29/2021

CHLOROBROMOMETHANE†

Chemical Identification
CAS #	74-97-5
Formula	CH₂BrCl
Synonyms	bromochloromethane; methylene chlorobromide; methylene bromochloride; mono-chloro-mono-bromo-methane; chloromethylbromide; CB; CBM; Halon 1011

Physical Properties
Physical description	Colorless to pale-yellow liquid with a chloroform-like odor.
Boiling point	155°F	Molecular weight	129.4
Freezing point/melting point	-124°F	Vapor pressure	115 mmHg
Flash point		Vapor density	4.46
Specific gravity	1.93	Ionization potential	10.77 eV
Lower explosive limit (LEL)		Upper explosive limit (UEL)
NFPA health rating		NFPA fire rating
NFPA reactivity rating		NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	0627
Sampling group
Sampler/Sampling media	CSC tube (100/50 mg) [SKC 226-01]
Sampling time^*	480 min
Sampling volume (TWA)^*	60 L
Sampling flow rate (TWA)^*	0.01-0.2 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-ECD
Method reference	NIOSH 1003 (partially validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Detector tube	Infrared spectrophotometer	Infrared spectrophotometer
Model/Type	Gastec 136L; 136H; 136L	Gastec 135	Miran 1A	Miran 103
Sampling information (see manufacturer instructions)	136LA 1-36 ppm; 136H 10-600 ppm; 136L 2.5-200 ppm	20-350 ppm range	0.7 ppm@8.4µm	0-400 ppm@8.1µm

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	200 ppm (1050 mg/m³)	REL-TWA	200 ppm (1050 mg/m³)	TLV-TWA		PEL-TWA	200 ppm (1050 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	N	Skin notation	N
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes: Visit the ACGIH TLV site for specific data		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	2000 ppm
Carcinogenic classifications: EPA-D		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Bromochloromethane

NIOSH: Pocket Guide to Chemical Hazards - Chlorobromomethane

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Chlorobromomethane. See annual publication for most recent information.
NIOSH: Occupational Health Guideline for Chlorobromomethane. 1978.

Last Updated Date : 04/30/2024

ETHYL BROMIDE†

Chemical Identification
CAS #	74-96-4
Formula	C₂H₅Br
Synonyms	bromoethane; monobromoethane

Physical Properties
Physical description	Colorless to yellow liquid with an ether-like odor.
Boiling point	101°F	Molecular weight	109
Freezing point/melting point	-182°F	Vapor pressure	375 mmHg
Flash point	-10°F	Vapor density	3.76
Specific gravity	1.46	Ionization potential	10.29 eV
Lower explosive limit (LEL)	6.8%	Upper explosive limit (UEL)	8.0%
NFPA health rating	3	NFPA fire rating	3
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1090
Sampling group
Sampler/Sampling media	CSC tube (100/50 mg) [SKC 226-01]
Sampling time^*
Sampling volume (TWA)^*	0.5-4 L
Sampling flow rate (TWA)^*	0.01-0.2 L/min
Sampling volume (STEL/Peak/C)^*	3 L
Sampling flow rate (STEL/Peak/C)^*	0.2 L/min
Analytical method instruments	GC-FID
Method reference	NIOSH 1011 (partially validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Infrared spectrophotometer	Organic vapor analyzer
Model/Type	Gastec 136L; 136H; 136L	Miran 1A & 1B
Sampling information (see manufacturer instructions)	136LA 1-36 ppm; 136H 10-600 ppm; 136L 2.5-200 ppm	0.8 ppm@8 µm

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	200 ppm (890 mg/m³)	REL-TWA	200 ppm	TLV-TWA	5 ppm [1990]	PEL-TWA	5 ppm (22 mg/m³)
PEL-STEL		REL-STEL	250 ppm	TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	Y	Skin notation	Y
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	2000 ppm
Carcinogenic classifications: IARC-3, TLV-A3		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Ethyl bromide

NIOSH: Pocket Guide to Chemical Hazards - Ethyl Bromide

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Ethyl bromide. See annual publication for most recent information.

Last Updated Date : 12/28/2020

METHYL MERCAPTAN (METHANETHIOL)†

Chemical Identification
CAS #	74-93-1
Formula	CH₄S
Synonyms	mercaptomethane; methanethiol; methyl sulfhydrate

Physical Properties
Physical description	Colorless gas with a disagreeable odor like garlic or rotten cabbage.
Boiling point	42.7°F	Molecular weight	48.1
Freezing point/melting point	-189.4°F	Vapor pressure	1.7 atm
Flash point	0°F	Vapor density	1.66
Specific gravity	0.90 at 42.8°F	Ionization potential	9.44 eV
Lower explosive limit (LEL)	3.9%	Upper explosive limit (UEL)	21.8%
NFPA health rating	4	NFPA fire rating	4
NFPA reactivity rating	1	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1643
Sampling group
Sampler/Sampling media	GFF (37 mm Gelman Type A) coated with mercuric acetate [SKC 225-9007]
Sampling time^*	100 min
Sampling volume (TWA)^*	20 L
Sampling flow rate (TWA)^*	0.2 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-FPD
Method reference	OSHA 26 (fully validated)
Notes	Protect samples from light until analysis.
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tubes	Detector tubes	Detector tubes	Detector tube	Detector tube	CMS Chip
Model/Type	Dräger - Mercaptan 0.1/a, 8103281; Mercaptan 0.5/a, 6728981; Mercaptan 20/a, 8101871	Gastec 70L, 70	Gastec 71, 71H	Matheson-Kitagawa 8014-164SA	Matheson-Kitagawa 8014-164SH	Mercaptan, 0.25-6 ppm range
Sampling information (see manufacturer instructions)	0.1/a: 2 or 10 strokes, approx 0.1-15 ppm range, 0.5/a: 20 strokes, approx 0.2-5 ppm range, 20/a: 10 strokes, approx 5-100 ppm range. Uncertainty 16%	70L: 0.5-4 strokes. 70: 1-10 strokes, 0.2-120 ppm, 16% for 5-40 ppm, 8% for 40-120 ppm.	71: 0.5-10 strokes, 0.1-140 ppm range, uncertainty 16% for 2.5-20 ppm, 8% for 20-70 ppm. 71H: 0.5-2 strokes, 2-2700 ppm range, uncertainty 16% for 50-200 ppm, 8% for 200-1000 ppm.	follow mfr instructions, approx 5-140 ppm range	follow mfr instructions, approx 50-1000 ppm range

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	0.5 ppm (1 mg/m³) [Construction and Maritime Industries only]	REL-TWA		TLV-TWA	0.5 ppm [2003]	PEL-TWA	0.5 ppm (1 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C	10 ppm (20 mg/m³) [General Industry only]	REL-C	0.5 ppm (1 mg/m³) [15 minutes]	TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	N	Skin notation	N
Notes: The OSHA PEL applies to Construction and Maritime Industries only. See 29 CFR 1910.1000 Table Z-1, 29 CFR 1926.55 Table 1 and 29 CFR 1915.1000 Table Z-Shipyards.		Notes:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	150 ppm
Carcinogenic classifications: Not listed		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 0.005 ppm/25 ppm/100 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methyl mercaptan

NIOSH: Pocket Guide to Chemical Hazards - Methyl mercaptan

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methyl mercaptan. See annual publication for most recent information.
(metabolism)
Levitt, M.D., Furne, J., Springfield, J., Suarez, F. and DeMaster, E.: Detoxification of hydrogen sulfide and methanethiol in the cecal mucosa. J. Clin. Invest. 104(8): 1107-1114, 1999.
Picton, R., Eggo, M.C., Merrill, G.A., Langman, M.J.S. and Singh, S.: Mucosal protection against sulphide: importance of the enzyme rhodanese. Gut 50(2): 201-205, 2002.
(fatalities)
Litovitz, T.L., et al.: 2001 Annual Report of the American Association of Poison Control Centers Toxic Exposure Surveillance System. Am. J. Emerg. Med. 20(5): 391-452, 2002.

Last Updated Date : 06/08/2022

HYDROGEN CYANIDE†

Chemical Identification
CAS #	74-90-8
Formula	CHN
Synonyms	formonitrile; hydrocyanic acid; prussic acid

Physical Properties
Physical description	Colorless or pale-blue liquid or gas (above 78°F) with a bitter, almond-like odor.
Boiling point	78°F (96%)	Molecular weight	27
Freezing point/melting point	7°F (96%)	Vapor pressure	630 mmHg
Flash point	0°F (96%)	Vapor density
Specific gravity	0.69	Ionization potential	13.60 eV
Lower explosive limit (LEL)	5.6%	Upper explosive limit (UEL)	40%
NFPA health rating	4	NFPA fire rating	4
NFPA reactivity rating	1	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1440
Sampling group
Sampler/Sampling media	SKC ULTRA II Hydrogen Cyanide Passive Sampler, Soda Lime, 600 mg [SKC 590-400]
Sampling time^*	240 min
Sampling volume (TWA)^*	6.816 L
Sampling flow rate (TWA)^*	0.0284 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	IC
Method reference	OSHA 1015 (fully validated)
Notes	If hydrogen sulfide is present at its PEL, there could be an interference and a thiocyanate peak will be seen at the same IC conditions ran for cyanide.
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method	Available

On-Site Screening Techniques
Device	Detector tube	CMS Chip
Model/Type	Dräger - Cyanide 2/a, 6728791	Hydrocyanic acid, 2-50 ppm range
Sampling information (see manufacturer instructions)	10 strokes, approx 1-15 mg/m³ range, uncertainty 33-49%

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	10 ppm (11 mg/m³)	REL-TWA		TLV-TWA		PEL-TWA
PEL-STEL		REL-STEL	4.7 ppm (5 mg/m³)	TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C	4.7 ppm [1991]	PEL-C	4.7 ppm (5 mg/m³)
Skin notation	Y	Skin notation	Y	Skin notation	Y	Skin notation	Y
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	50 ppm
Carcinogenic classifications: EPA-II		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: --/10 ppm/25 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Hydrocyanic acid, aqueous solution, with not more than 20% hydrogen cyanide

NIOSH: Pocket Guide to Chemical Hazards - Hydrogen cyanide

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Hydrogen cyanide and cyanide salts, as CN. See annual publication for most recent information.
Agency for Toxic Substances and Disease Registry (ATSDR): Toxicological Profile for Cyanide (Update). PHS, U.S. DHHS, Atlanta, GA, 1997.
U.S. EPA Technology Transfer Network Air Toxics Website: Cyanide Compounds.
Albin, R.L.: Basal ganglia neurotoxins. Neurol. Clin. 18(3): 665-680, 2000

Last Updated Date : 12/31/2020

METHYLAMINE†

Chemical Identification
CAS #	74-89-5
Formula	CH₅N
Synonyms	aminomethane; methylamine (anhydrous); methylamine (aqueous); monomethylamine

Physical Properties
Physical description	Colorless gas with a fish- or ammonia-like odor.
Boiling point	20.3°F	Molecular weight	31.1
Freezing point/melting point	-136°F	Vapor pressure	3.0 atm
Flash point		Vapor density	1.08
Specific gravity	0.693 at 20.3°F	Ionization potential	8.97 eV
Lower explosive limit (LEL)	4.9%	Upper explosive limit (UEL)	20.7%
NFPA health rating	3	NFPA fire rating	4
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1665
Sampling group
Sampler/Sampling media	XAD-7 tube (80/40 mg) coated with 10% NBD chloride [SKC 226-96]
Sampling time^*	50 min
Sampling volume (TWA)^*	10 L
Sampling flow rate (TWA)^*	0.2 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	HPLC
Method reference	OSHA 40 (fully validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Infrared spectrophotometer
Model/Type	Matheson-Kitagawa 8014-222S	Miran 1A & 1B
Sampling information (see manufacturer instructions)	1-40 ppm range	1.9 ppm@3.4 µm

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	10 ppm (12 mg/m³)	REL-TWA	10 ppm (12 mg/m³)	TLV-TWA	5 ppm [2012]	PEL-TWA	5 ppm (6.4 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL	15 ppm [2012]	PEL-STEL	15 ppm (19 mg/m³)
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	N	Skin notation	N
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	100 ppm
Carcinogenic classifications: Not listed		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 10 ppm/100 ppm/500 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methylamine, anhydrous

NIOSH: Pocket Guide to Chemical Hazards - Methylamine

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methylamine. See annual publication for most recent information.

Last Updated Date : 01/29/2021

METHYL IODIDE†

Chemical Identification
CAS #	74-88-4
Formula	CH₃I
Synonyms	iodomethane; monoiodomethane

Physical Properties
Physical description	Colorless liquid with a pungent, ether-like odor.
Boiling point	109°F	Molecular weight	141.94
Freezing point/melting point	-88°F	Vapor pressure	400 mmHg
Flash point		Vapor density
Specific gravity	2.28	Ionization potential	9.54 eV
Lower explosive limit (LEL)	10%	Upper explosive limit (UEL)	15%
NFPA health rating	3	NFPA fire rating	0
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1772
Sampling group
Sampler/Sampling media	CSC tube (100/50 mg) [SKC 226-01]
Sampling time^*
Sampling volume (TWA)^*	15-50 L
Sampling flow rate (TWA)^*	0.01-1 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-FID
Method reference	NIOSH 1014 (partially validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Infrared spectrophotometer	Detector tube
Model/Type	Miran 1A & 1B	Matheson-Kitagawa 8014-176S
Sampling information (see manufacturer instructions)	1.8 ppm@3.4µm	5-40 ppm range

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	5 ppm (28 mg/m³)	REL-TWA	2 ppm (10 mg/m³)	TLV-TWA	2 ppm [1978]	PEL-TWA	2 ppm (10 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	Y	Skin notation	Y	Skin notation	Y	Skin notation	Y
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes: CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 1.7 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens.		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	100 ppm
Carcinogenic classifications: IARC-3, NIOSH-Ca		Notes: Ca
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 25 ppm/50 ppm/125 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methyl iodide

NIOSH: Pocket Guide to Chemical Hazards - Methyl iodide

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methyl iodide. See annual publication for most recent information.

Last Updated Date : 01/29/2021

METHYL CHLORIDE†

Chemical Identification
CAS #	74-87-3
Formula	CH₃Cl
Synonyms	chloromethane; monochloromethane

Physical Properties
Physical description	Colorless gas with a faint, sweet odor which is not noticeable at dangerous concentrations.
Boiling point	-12°F	Molecular weight	50.5
Freezing point/melting point	-144°F	Vapor pressure	5.0 atm
Flash point	-49.0°F	Vapor density	1.78
Specific gravity	0.997 at -11.2°F	Ionization potential	11.28 eV
Lower explosive limit (LEL)	8.1%	Upper explosive limit (UEL)	17.4%
NFPA health rating	2	NFPA fire rating	4
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1710
Sampling group
Sampler/Sampling media	2 CSC tubes in series (first tube 400/200 mg, second tube 100/50 mg) [SKC 226-09 & SKC 226-01]
Sampling time^*
Sampling volume (TWA)^*	0.4-3 L
Sampling flow rate (TWA)^*	0.01-0.1 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-FID
Method reference	NIOSH 1001 (fully validated)
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Detector tube
Model/Type	Gastec 51	Gastec 51L
Sampling information (see manufacturer instructions)	1 stroke, approx 10-480 ppm	1 or 2 strokes, approx 1-86 ppm

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	100 ppm (210 mg/m³)	REL-TWA		TLV-TWA	50 ppm [1992]	PEL-TWA	50 ppm (105 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL	100 ppm [1992]	PEL-STEL	100 ppm (210 mg/m³)
PEL-C	200 ppm; 300 ppm (Peak - 5 min in any 3 hrs)	REL-C		TLV-C		PEL-C	300 ppm
Skin notation	N	Skin notation	N	Skin notation	Y	Skin notation	N
Notes: Ceiling value applies only to OSHA General Industry standard. TWA applies to OSHA's General Industry and Maritime standards. See 29 CFR 1910.1000 Table Z-2 and 29 CFR 1915.1000 Table Z-Shipyards.		Notes: CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 1.6 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens.		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	2000 ppm
Carcinogenic classifications: IARC-3, NIOSH-Ca, TLV-A4, EPA-D; CBD		Notes: Ca
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: 150 ppm/1000 ppm/3000 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methyl chloride

NIOSH: Pocket Guide to Chemical Hazards - Methyl chloride

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methyl chloride. See annual publication for most recent information.
EPA Air Toxics Website: Methyl Chloride (Chloromethane). U.S. Environmental Protection Agency Technology Transfer Network.
Nelson, H.H., et al., Ethnic differences in the prevalence of the homozygous deleted genotype of glutathione S-transferase theta. Carcinogenesis 16(5): 143-1245, 1995.
No authors: Methyl chloride. IARC Monogr. Eval. Carcinog. Risks Hum. 71(Pt. 2): 737-747, 1999.
Pohanish, R.P. (editor): Methyl Chloride. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1537-1540.

Last Updated Date : 01/29/2021

ETHYLENE

Chemical Identification
CAS #	74-85-1
Formula	C₂H₄
Synonyms	ethene; acetene

Physical Properties
Physical description	Colorless gas with a sweet odor.
Boiling point	-154.7°F	Molecular weight	28.05
Freezing point/melting point	-272.4°F	Vapor pressure
Flash point	-213°F (approx)	Vapor density
Specific gravity	0.569 at -154.84°F	Ionization potential
Lower explosive limit (LEL)	2.75%	Upper explosive limit (UEL)	28.6%
NFPA health rating	2	NFPA fire rating	4
NFPA reactivity rating	2	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)
Sampling group
Sampler/Sampling media
Sampling time^*
Sampling volume (TWA)^*
Sampling flow rate (TWA)^*
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments
Method reference
Notes
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Detector tube	Detector tubes	Detector tube	Detector tube
Model/Type	Dräger - Ethylene 0.1/a, 8101331	Dräger - Ethylene 50/a, 6728051	Gastec 172L, 172, 171	Matheson-Kitagawa 8014-108SA	Matheson-Kitagawa 8014-280S
Sampling information (see manufacturer instructions)	20 strokes, approx 0.2-5 ppm range; uncertainty 49%	3 strokes, approx 50-2500 ppm range, uncertainty 32%	172L: 1 stroke, 5-800 ppm range, uncertainty 16% for 25-200 ppm, 8% for 200-800 ppm. 172: 1 stroke, 5-800 ppm range, uncertainty 16% for 25-200 ppm, 8% for 200-800 ppm. 171: 1 stroke, 0.1-2% range. 103: 0.5-2 strokes, 0.35-16.8% range	follow mfr instructions, approx 20-1200 ppm range	follow mfr instructions, approx 20-2000 ppm range

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA		REL-TWA		TLV-TWA	200 ppm [2001]	PEL-TWA
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	NA	Skin notation	N	Skin notation	N
Notes: Ethylene is classified as a simple asphyxiant and exposure is addressed in OSHA Construction and Maritime standards only. For OSHA's construction regulations, see 29 CFR 1926.55 Table 1: [E] The limiting factor is the available oxygen which shall be at least 19.5% and be within the requirements addressing explosion in 29 CFR 1926. For OSHA's maritime regulations, see 29 CFR 1915.1000 Table Z-Shipyards: [E] The limiting factor is the available oxygen which shall be at least 18% and be within the requirements addressing explosion in 29 CFR 1915, Subpart B.		Notes: Not established		Notes:		Notes: See footnote [h]: A number of gases and vapors, when present in high concentrations, act primarily as asphyxiants without other adverse effects. A concentration limit is not included for each material because the limiting factor is the available oxygen. (Several of these materials present fire or explosion hazards.)
Health factors: See NIH-NLM PubChem.		IDLH
Carcinogenic classifications: TLV-A4		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Ethylene

NIOSH: Pocket Guide to Chemical Hazards - Ethylene

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Ethylene. See annual publication for most recent information.

Last Updated Date : 01/31/2018

METHYL BROMIDE†

Chemical Identification
CAS #	74-83-9
Formula	CH₃Br
Synonyms	bromomethane; monobromomethane

Physical Properties
Physical description	Colorless gas with a chloroform-like odor at high concentrations.
Boiling point	38°F	Molecular weight	94.95
Freezing point/melting point	-137°F	Vapor pressure	1.9 atm
Flash point		Vapor density	3.36
Specific gravity	1.73 (liquid at 32°F)	Ionization potential	10.54 eV
Lower explosive limit (LEL)	10%	Upper explosive limit (UEL)	16%
NFPA health rating	3	NFPA fire rating	1
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1680
Sampling group
Sampler/Sampling media	2 Anasorb 747 sampling tubes (6 mm glass tubes, the front tube contains 400 and the back 200 mg of sorbent) connected in series [SKC 226-82], tube holder [SKC 222-3L-1], Type D cover [SKC 224-29D]
Sampling time^*	60 min
Sampling volume (TWA)^*	3 L
Sampling flow rate (TWA)^*	0.05-0.2 L/min
Sampling volume (STEL/Peak/C)^*	3 L
Sampling flow rate (STEL/Peak/C)^*	0.05-0.2 L/min
Analytical method instruments	GC-FID
Method reference	OSHA PV2040 (partially validated)
Notes	The Anasorb tubes should be separated and capped after sampling. Tubes should be refrigerated as soon after sampling as possible and shipped cold to the SLTC.
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device	Detector tube	Detector tube
Model/Type	Gastec 136LA	Matheson-Kitagawa 8014-157SB
Sampling information (see manufacturer instructions)	1-2 strokes, 0.2-36 ppm range, uncertainty 16% for 1-6 ppm, 8% for 6-18 ppm	1,2 or 4 strokes, approx 0.2-80 ppm rang

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA		REL-TWA		TLV-TWA	1 ppm [1994]	PEL-TWA	1 ppm (3.88 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C	20 ppm (80 mg/m³)	REL-C		TLV-C		PEL-C	20 ppm
Skin notation	Y	Skin notation	N	Skin notation	Y	Skin notation	Y
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes: CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION (LOQ 4.7 ppm). See Appendix A, NIOSH Potential Occupational Carcinogens. See also Appendix G: 1989 Air Contaminants Update Project - Exposure Limits NOT in Effect		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	250 ppm
Carcinogenic classifications: IARC-3, NIOSH-Ca, TLV-A4, EPA-D		Notes: Ca
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3: --/50 ppm/200 ppm

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Methyl bromide

NIOSH: Pocket Guide to Chemical Hazards - Methyl bromide

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Methyl bromide. See annual publication for most recent information.
International Chemical Safety Cards (WHO/IPCS/ILO): Methyl Bromide.
EPA Air Toxics Website: Methyl Bromide (Bromomethane). U.S. Environmental Protection Agency Technology Transfer Network.
Garnier, R., Rambourg-Schepens, M.O., Muller, A. and Hallier, E.: Glutathione transferase activity and formation of macromolecular adducts in two cases of acute methyl bromide poisoning. Occup. Environ. Med. 53(3): 211-215, 1996.
Lenhart, S.W. and Gagnon, Y.T.: Health hazard evaluation of methyl bromide soil fumigations. Appl. Occup. Environ. Med. 14(7): 407-412, 1999.
No authors: Methyl bromide. IARC Monogr. Eval. Carcinog. Risks Hum. 71(Pt. 2): 721-735, 1999.
Pohanish, R.P. (editor): Methyl Bromide. In, Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1531-1534.

Last Updated Date : 01/29/2021

PROPANE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

CHLOROBROMOMETHANE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

ETHYL BROMIDE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

METHYL MERCAPTAN (METHANETHIOL)†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

HYDROGEN CYANIDE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

METHYLAMINE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

METHYL IODIDE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

METHYL CHLORIDE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

ETHYLENE

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References

METHYL BROMIDE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References