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Pyridine

Synonyms & Trade Names
Azabenzene, Azine
CAS No.
110-86-1
RTECS No.
DOT ID & Guide
1282 129
Formula
C₅H₅N
Conversion
1 ppm = 3.24 mg/m3
IDLH
1000 ppm
See: 110861
Exposure Limits
NIOSH REL
TWA 5 ppm (15 mg/m3)
OSHA PEL
TWA 5 ppm (15 mg/m3)
Measurement Methods
NIOSH 1613;
OSHA 7
See: NMAM or OSHA Methods
Physical Description
Colorless to yellow liquid with a nauseating, fish-like odor.
Molecular Weight
79.1
Boiling Point
240°F
Freezing Point
-44°F
Solubility
Miscible
Vapor Pressure
16 mmHg
Ionization Potential
9.27 eV
Specific Gravity
0.98
Flash Point
68°F
Upper Explosive Limit
12.4%
Lower Explosive Limit
1.8%
Class IB Flammable Liquid: Fl.P. below 73°F and BP at or above 100°F.
Incompatibilities & Reactivities
Strong oxidizers, strong acids
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,
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
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

See also
INTRODUCTION   ICSC CARD: 0323   MEDICAL TESTS: 0200
Page last reviewed: October 30, 2019