NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

Pyridine

CAS
110-86-1

C5H5N

RTECS
UR8400000
Synonyms & Trade Names

Azabenzene, Azine
DOT ID & Guide
1282 / 129

Exposure
Limits

NIOSH REL: TWA 5 ppm (15 mg/m3)
OSHA PEL: TWA 5 ppm (15 mg/m3)
IDLH
1000 ppm See: 110861
Conversion
1 ppm = 3.24 mg/m3
Physical Description
Colorless to yellow liquid with a nauseating, fish-like odor.
MW: 79.1
BP: 240°F
FRZ: -44°F
Sol: Miscible
VP: 16 mmHg
IP: 9.27 eV

Sp.Gr: 0.98
Fl.P: 68°F
UEL: 12.4%
LEL: 1.8%

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

Strong oxidizers, strong acids
Measurement Methods
NIOSH 1613; OSHA 7
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
Provide: Eyewash, Quick drench
First Aid
(See procedures)
Eye: Irrigate immediately
Skin: Water flush immediately
Breathing: Respiratory support
Swallow: Medical attention immediately
Respirator Recommendations
NIOSH/OSHA
Up to 125 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 50 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 1000 ppm:
(APF = 2000) Any supplied-air respirator that has a full facepiece and is 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, skin absorption, ingestion, skin and/or eye contact
Symptoms
Irritation eyes; headache, anxiety, dizziness, insomnia; nausea, anorexia; dermatitis; liver, kidney damage
Target Organs
Eyes, skin, central nervous system, liver, kidneys, gastrointestinal tract,
See also: INTRODUCTION   See ICSC CARD: 0323   See MEDICAL TESTS: 0200