BENZENE‡

Chemical Identification
Chemical Identification
CAS # 71-43-2
Formula

C₆H₆

Synonyms

benzine; benzol; cyclohexatriene; phenyl hydride

Physical Properties
Physical Properties
Physical description Highly flammable colorless to light-yellow liquid with a petroleum-like odor.
Boiling point 176.2°F Molecular weight 78.11
Freezing point/melting point 41.9°F Vapor pressure 75 mmHg
Flash point 12°F Vapor density 2.77
Specific gravity 0.88 Ionization potential 9.24 eV
Lower explosive limit (LEL) 1.2% Upper explosive limit (UEL) 8%
NFPA health rating 2 NFPA fire rating 3
NFPA reactivity rating 0 NFPA special instruction
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs
Monitoring Methods Used by OSHA
Monitoring Methods Used by OSHA
Analyte code (IMIS no.) 0320 0320
Sampling group OVSG-1
Sampler/Sampling media CSC tube (100/50 mg) [SKC 226-01] SKC 575-002 Passive Sampler [SKC 575-002]
Sampling time*

240 min (15 min STEL)

240 min TWA; 10 min Peak; 15 min STEL (Note: SKC 575-002 Passive Samplers  must be exposed for at least 10 min)

Sampling volume (TWA)*

12 L

Sampling flow rate (TWA)*

0.05 L/min

Sampling volume (STEL/Peak/C)*

0.75 L

Sampling flow rate (STEL/Peak/C)*

0.05 L/min

Analytical method instruments GC-FID GC-FID
Method reference OSHA 5000 (fully validated) OSHA 1005 v.2.1 (fully validated)
Notes

To obtain sampling and analytical error similar to that available with active sampling, knowledge of the atmospheric pressure and temperature are required, and these should be obtained using NIST-traceable devices.

If that is not possible, temperature is assumed to be 22.2 °C, and the atmospheric pressure is estimated based on the elevation of the sampling location.

When estimates are used in place of traceable measurements the sampling and analytical error associated with passive sampling is substantially increased, and this makes it more difficult to demonstrate over exposures after considering the 95% lower confidence limit.

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.

Wipe Method
Wipe Method
Sampler/Sampling media
Bulk Method
Bulk Method
On-Site Screening Techniques
On-Site Screening Techniques
Device Detector tube Detector tube Detector tube CMS Chip CMS Chip
Model/Type Gastec 121 Matheson-Kitagawa 8014-118SC Dräger - Benzene 5/b 6728071 Benzene, 0.05-2.5 ppm range; Benzene, 0.2-10 ppm range Benzene, 0.5-10 ppm range; Benzene, 10-250 ppm range
Sampling information
(see manufacturer instructions)
1-4 strokes, 0.5-120 ppm range, uncertainty 16.4% for 50-20 ppm, 8.2% for 20-60 ppm Follow mfr instructions, 0.2-100 ppm range 20 strokes, 1-50 ppm range, 25% uncertainty
Exposure Limits
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

1 ppm

REL-TWA

0.1 ppm

TLV-TWA

0.5 ppm [1996]

PEL-TWA

1 ppm

PEL-STEL

5 ppm

REL-STEL

1 ppm

TLV-STEL

2.5 ppm [1996]

PEL-STEL

5 ppm

PEL-C REL-C TLV-C PEL-C
Skin notation

N

Skin notation

N

Skin notation

Y

Skin notation

Y

Notes:

See 29 CFR 1910.1028, Benzene.

See 29 CFR 1910.1000 Table Z-2 for any operations or sectors where the exposure limits in 1910.1028 are stayed or otherwise not in effect.

Notes:

CARCINOGEN (Ca): REDUCE EXPOSURE TO LOWEST FEASIBLE CONCENTRATION. See Appendix A, NIOSH Potential Occupational Carcinogens.

Notes:

BEI®

Notes:

Also See California Code of Regulations, Title 8, Sec 5218.

Health factors:  See NIH-NLM PubChem. IDLH

500 ppm

Carcinogenic classifications: EPA-A; K, IARC-1, NIOSH-Ca, NTP-K, OSHA-Ca, TLV-A1 Notes:

Ca

AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

50 ppm/150 ppm/1000 ppm

Additional Resources and Literature References
Additional Resources and Literature References

NOAA: CAMEO Chemicals - Benzene

NIOSH: Pocket Guide to Chemical Hazards - Benzene

Literature References

  • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Benzene. See annual publication for most recent information.
  • Occupational Health Guidelines for Chemical Hazards. DHHS/ NIOSH Publication No. 81-123, (January 1981).
  • EPA: Hazard Summary - Benzene.
  • ATSDR: Toxicological Profile for Benzene. 2007.
  • ANSI Z37.4, Acceptable Concentrations of Benzene.
  • Costatini AS, et al. Exposure to benzene and risk of breast cancer among shoe factory workers in Italy. Tumori. 95(1):8-12, January-February 2009.
  • Ji Z, et al. Comparison of aneuploidies of chromosomes 21, X, and Y in the blood lymphocytes and sperm of workers exposed to benzene. Environ Mol Mutagen. 53(3):218-26, April 2012.
  • Lupo PJ, et al. Maternal exposure to ambient levels of benzene and neural tube defects among offspring: Texas, 1999-2004. Environ Health Perspect. 119(3):397-402, March 2011.
  • Marchetti F, et al. Occupational exposure to benzene and chromosomal structural aberrations in the sperm of Chinese men. Environ Health Perspect. 120(2):229-34, February, 2012.
  • Peplonska B, et al. Occupational exposure to organic solvents and breast cancer in women. Occup Environ Med. 67(11):722-9, November, 2010.
  • Prochazka M, et al. Occupational exposures and risk of acoustic neuroma. Occup Environ Med. 67(11):766-71, November, 2010.

Last Updated Date : 04/06/2021