NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

n-Butyl mercaptan

CAS
109-79-5

CH3CH2CH2CH2SH

RTECS
EK6300000
Synonyms & Trade Names

Butanethiol, 1-Butanethiol, n-Butanethiol, 1-Mercaptobutane
DOT ID & Guide
2347 / 130

Exposure
Limits

NIOSH REL: C 0.5 ppm (1.8 mg/m3) [15-minute]
OSHA PEL: TWA 10 ppm (35 mg/m3)
IDLH
500 ppm See: 109795
Conversion
1 ppm = 3.69 mg/m3
Physical Description
Colorless liquid with a strong, garlic-, cabbage-, or skunk-like odor.
MW: 90.2
BP: 209°F
FRZ: -176°F
Sol: 0.06%
VP: 35 mmHg
IP: 9.15 eV

Sp.Gr: 0.83
Fl.P: 35°F
UEL: ?
LEL: ?

Class IB Flammable Liquid: Fl.P. below 73F and BP at or above 100F.
Incompatibilities & Reactivities

Strong oxidizers (such as dry bleaches), acids
Measurement Methods
NIOSH 2525, 2542
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
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 promptly
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 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
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
Irritation eyes, skin; muscle weakness, malaise (vague feeling of discomfort), sweating, nausea, vomiting, headache, confusion; in animals: narcosis, incoordination, lassitude (weakness, exhaustion); cyanosis, pulmonary irritation; liver, kidney damage
Target Organs
Eyes, skin, respiratory system, central nervous system, liver, kidneys
See also: INTRODUCTION   See ICSC CARD: 0018   See MEDICAL TESTS: 0033