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Ethyl mercaptan

Synonyms & Trade Names
Ethanethiol, Ethyl sulfhydrate, Mercaptoethane
CAS No.
75-08-1
RTECS No.
DOT ID & Guide
2363 129
Formula
CH₃CH₂SH
Conversion
1 ppm = 2.54 mg/m3
IDLH
500 ppm
See: 75081
Exposure Limits
NIOSH REL
C 0.5 ppm (1.3 mg/m3) [15-minute]
OSHA PEL
C 10 ppm (25 mg/m3) See Appendix G
Measurement Methods
NIOSH 2542
See: NMAM or OSHA Methods
Physical Description
Colorless liquid with a strong, skunk-like odor. [Note: A gas above 95°F.]
Molecular Weight
62.1
Boiling Point
95°F
Freezing Point
-228°F
Solubility
0.7%
Vapor Pressure
442 mmHg
Ionization Potential
9.29 eV
Specific Gravity
0.84
Flash Point
-55°F
Upper Explosive Limit
18.0%
Lower Explosive Limit
2.8%
Class IA Flammable Liquid: Fl.P. below 73°F and BP below 100°F.
Incompatibilities & Reactivities
Strong oxidizers [Note: Reacts violently with calcium hypochlorite.]
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
irritation mucous membrane; headache, nausea; In Animals: incoordination, lassitude (weakness, exhaustion); liver, kidney damage; cyanosis; narcosis
Target Organs
Eyes, respiratory system, liver, kidneys, blood
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet (flammable)
Change:No recommendation
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Soap wash immediately
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH

Up to 5 ppm:
(APF = 10) Any chemical cartridge respirator with organic vapor cartridge(s)
(APF = 10) Any supplied-air respirator

Up to 12.5 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode
(APF = 25) Any powered, air-purifying respirator with organic vapor cartridge(s)

Up to 25 ppm:
(APF = 50) Any chemical cartridge respirator with a full facepiece and organic vapor cartridge(s)
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
(APF = 50) Any supplied-air respirator that has a tight-fitting facepiece and is operated in a continuous-flow mode
(APF = 50) Any powered, air-purifying respirator with a tight-fitting facepiece and organic vapor cartridge(s)
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

Up to 500 ppm:
(APF = 1000) Any supplied-air respirator operated in a pressure-demand or other positive-pressure mode

Emergency or planned entry into unknown concentrations or IDLH conditions:
(APF = 10,000) Any self-contained breathing apparatus that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode
(APF = 10,000) Any supplied-air respirator that has a full facepiece and is operated in a pressure-demand or other positive-pressure mode in combination with an auxiliary self-contained positive-pressure breathing apparatus

Escape:
(APF = 50) Any air-purifying, full-facepiece respirator (gas mask) with a chin-style, front- or back-mounted organic vapor canister
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0470   MEDICAL TESTS: 0099
Page last reviewed: October 30, 2019