NAPHTHALENE | Occupational Safety and Health Administration

NAPHTHALENE†

Chemical Identification
CAS #	91-20-3
Formula	C₁₀H₈
Synonyms	diesel exhaust component; white tar; naphthalin; tar camphor

Physical Properties
Physical description	A white crystalline volatile solid with a strong coal-tar odor.
Boiling point	424°F	Molecular weight	128.2
Freezing point/melting point	176°F	Vapor pressure	0.08 mmHg
Flash point	174°F	Vapor density	4.42
Specific gravity	1.15	Ionization potential	8.12 eV
Lower explosive limit (LEL)	0.9%	Upper explosive limit (UEL)	5.9%
NFPA health rating	2	NFPA fire rating	2
NFPA reactivity rating	0	NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1810
Sampling group
Sampler/Sampling media	Chromosorb® 106 (100/50 mg) [SKC 226-110]
Sampling time^*	50 min
Sampling volume (TWA)^*	10 L
Sampling flow rate (TWA)^*	0.2 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	GC-FID
Method reference	OSHA 35 (fully validated)
Notes	Submit as a separate sample.
Special requirements

^* All sampling instructions above are recommended guidelines for OSHA Compliance Safety and Health Officers (CSHOs), please see the corresponding OSHA method reference for complete details.

Bulk/Wipe Method
Wipe Sampler/Sampling media
Bulk Method

On-Site Screening Techniques
Device
Model/Type
Sampling information (see manufacturer instructions)

**Exposure Limits**
OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak		NIOSH REL Up to 10-hour TWA (ST) STEL (C) Ceiling		ACGIH TLV© 8-hour TWA (ST) STEL (C) Ceiling		CAL/OSHA PEL 8-hour TWA (ST) STEL (C) Ceiling Peak
PEL-TWA	10 ppm (50 mg/m³)	REL-TWA	10 ppm (50 mg/m³)	TLV-TWA	10 ppm (52 mg/m³) [2013]	PEL-TWA	0.1 ppm (0.5 mg/m³)
PEL-STEL		REL-STEL	15 ppm (75 mg/m³)	TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	Y	Skin notation	Y
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes:		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	250 ppm
Carcinogenic classifications: TLV-A4, EPA-CBD;C, IARC-2B, NTP-R		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Naphthalene

NIOSH: Pocket Guide to Chemical Hazards - Naphthalene

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Naphthalene. See annual publication for most recent information.
EPA: Hazard Summary - Naphthalene.
ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Naphthalene. See annual publication for most recent information.
ATSDR: Toxicological Profile for Naphthalene, 1-Methylnaphthalene and 2-Methylnaphthalene. 2005.
Egeghy, P.P., Hauf-Cabalo, L., Gibson, R. and Rappaport, S.M.: Benzene and naphthalene in air and breath as indicators of exposure to jet fuel. Occup. Environ. Med. 60(12): 969-976, 2003.
EPA: Integrated Risk Information System - Napthalene. 1998.
IARC Monographs on Evaluation of Carcinogenic Risks to Humans, Volume 82, Naphthalene, 2002
Marczynski, B. et al.: Genotoxic risk assessment in white blood cells of occupationally exposed workers before and after alteration of the polycyclic aromatic hydrocarbon (PAH) profile in the production material: comparison with PAH air and urinary metabolite levels. Int Arch Occup Environ Health 78(2): 97-108, 2005.
NIOSH: Occupational Health Guideline for Naphthalene. September 1978.
NTP: Toxicology and carcinogenesis studies of naphthalene in B6C3F1 mice (inhalation studies). Technical Report Series No. 410. NIH Publication No. 92-3141. (1992).
NTP: Report on Carcinogens - Napthalene.
Preuss, R., Angerer, J. and Drexler, H.: Naphthalene - an environmental and occupational toxicant. Int. Arch. Occup. Environ. Health 76(8): 556-576, 2003.

Last Updated Date : 01/05/2021

NAPHTHALENE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References