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Naphthalene

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Synonyms & Trade Names
Naphthalin, Tar camphor, White tar
CAS No.
91-20-3
RTECS No.
QJ0525000
DOT ID & Guide
1334 133(crude or refined)
2304 133(molten)
Formula
C₁₀H₈
Conversion
1 ppm = 5.24 mg/m3
IDLH
250 ppm
See: 91203
Exposure Limits
NIOSH REL
TWA 10 ppm (50 mg/m3) ST 15 ppm (75 mg/m3)
OSHA PEL
TWA 10 ppm (50 mg/m3) See Appendix G
Measurement Methods
NIOSH 1501;
OSHA 35
See: NMAM or OSHA Methods
Physical Description
Colorless to brown solid with an odor of mothballs. [Note: Shipped as a molten solid.]
Molecular Weight
128.2
Boiling Point
424°F
Melting Point
176°F
Solubility
0.003%
Vapor Pressure
0.08 mmHg
Ionization Potential
8.12 eV
Specific Gravity
1.15
Flash Point
174°F
Upper Explosive Limit
5.9%
Lower Explosive Limit
0.9%
Combustible Solid, but will take some effort to ignite.
Incompatibilities & Reactivities
Strong oxidizers, chromic anhydride
Exposure Routes
inhalation, skin absorption, ingestion, skin and/or eye contact
Symptoms
irritation eyes; headache, confusion, excitement, malaise (vague feeling of discomfort); nausea, vomiting, abdominal pain; irritation bladder; profuse sweating; jaundice; hematuria (blood in the urine), renal shutdown; dermatitis, optical neuritis, corneal damage
Target Organs
Eyes, skin, blood, liver, kidneys, central nervous system
Personal Protection/Sanitation
(See protection codes)
Skin:Prevent skin contact
Eyes:Prevent eye contact
Wash skin:When contaminated
Remove:When wet or contaminated
Change:Daily
First Aid
(See procedures)
Eye:Irrigate immediately
Skin:Molten flush immediately/solid-liquid soap wash promptly
Breathing:Respiratory support
Swallow:Medical attention immediately
Respirator Recommendations

NIOSH/OSHA

Up to 100 ppm:
(APF = 10) Any air-purifying half-mask respirator with organic vapor cartridge(s) in combination with an N95, R95, or P95 filter. The following filters may also be used: N99, R99, P99, N100, R100, P100.
Click here for information on selection of N, R, or P filters.*
(APF = 10) Any supplied-air respirator*

Up to 250 ppm:
(APF = 25) Any supplied-air respirator operated in a continuous-flow mode*
(APF = 50) Any air-purifying full-facepiece respirator equipped with organic vapor cartridge(s) in combination with an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
(APF = 25) Any powered, air-purifying respirator with an organic vapor cartridge in combination with a high-efficiency particulate filter.*
(APF = 50) Any self-contained breathing apparatus with a full facepiece
(APF = 50) Any supplied-air respirator with a full facepiece

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 having an N100, R100, or P100 filter.
Click here for information on selection of N, R, or P filters.
Any appropriate escape-type, self-contained breathing apparatus

Important additional information about respirator selection

See also
INTRODUCTION   ICSC CARD: 0667   MEDICAL TESTS: 0152
Page last reviewed: October 30, 2019
Content source: National Institute for Occupational Safety and Health