NITRIC OXIDE | Occupational Safety and Health Administration

Lapse in Appropriations

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NITRIC OXIDE†

Chemical Identification
CAS #	10102-43-9
Formula	NO
Synonyms	mononitrogen monoxide; nitrogen monoxide

Physical Properties
Physical description	Colorless gas.
Boiling point	-241°F	Molecular weight	30.01
Freezing point/melting point	-263°F	Vapor pressure	34.2 atm
Flash point		Vapor density	1.04
Specific gravity	1.27 at -238.36°	Ionization potential	9.27 eV
Lower explosive limit (LEL)		Upper explosive limit (UEL)
NFPA health rating	3	NFPA fire rating	0
NFPA reactivity rating	0	NFPA special instruction	OX: Possesses oxidizing properties
Vapor hazard ratio (VHR)
Historical exceedance percentage
Target organs

Monitoring Methods Used by OSHA
Analyte code (IMIS no.)	1890
Sampling group
Sampler/Sampling media	Sorbent tubes, 2 molecular sieve (triethanolamine) tubes and 1 oxidizer tube [SKC 226-40A]
Sampling time^*	240 min
Sampling volume (TWA)^*	6 L
Sampling flow rate (TWA)^*	0.025 L/min
Sampling volume (STEL/Peak/C)^*
Sampling flow rate (STEL/Peak/C)^*
Analytical method instruments	IC
Method reference	OSHA ID-190 (fully validated)
Notes	Submit as separate sample. Only the back tube can be analyzed for NO. The front is analyzed for NO₂ by request. Carefully label tubes before shipping to the SLTC. Do not submit oxidizer tube to the SLTC.
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	25 ppm (30 mg/m³)	REL-TWA	25 ppm (30 mg/m³)	TLV-TWA	25 ppm [1992]	PEL-TWA	25 ppm (30 mg/m³)
PEL-STEL		REL-STEL		TLV-STEL		PEL-STEL
PEL-C		REL-C		TLV-C		PEL-C
Skin notation	N	Skin notation	N	Skin notation	N	Skin notation	N
Notes: See 29 CFR 1910.1000 Table Z-1.		Notes:		Notes: BEI®		Notes:
Health factors: See NIH-NLM PubChem.		IDLH	100 ppm
Carcinogenic classifications: Not listed		Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:

Additional Resources and Literature References

NOAA: CAMEO Chemicals - Nitric oxide

NIOSH: Pocket Guide to Chemical Hazards - Nitric oxide

Literature References

ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Nitric oxide. See annual publication for most recent information.
Barbinova, L. and Baur, X.: Increase in exhaled nitric oxide (eNO) after work-related isocyanate exposure. Int. Arch. Occup. Environ. Health 79(5): 387-395, 2006.
Baur, X. and Barbinova, L.: Latex allergen exposure increases exhaled nitric oxide in symptomatic healthcare workers. Eur. Respir. J. 25(2): 309-316, 2005.
Clark, R.H., et al.: Low-dose nitric oxide therapy for persistent pulmonary hypertension of the newborn. N. Engl. J. Med. 342(7): 469-474, 2000.
Griffiths, M.J.D. and Evans, T.W.: Inhaled nitric oxide therapy in adults. N. Engl. J. Med. 353(25): 2683-2695, 2005.
Maniscalco, M., Grieco, L., Galdi, A., Lundberg, J.O. and Sofia, M.: Increase in exhaled nitric oxide in shoe and leather workers at the end of the work-shift. Occup. Med. (Lond.) 54(6): 404-407, 2004.
Morishita, T., et al.: Nephrogenic diabetes insipidus in mice lacking all nitric oxide synthase isoforms. Proc. Natl. Acad. Sci. USA 102(30): 10616-10621, 2005.
Pohanish, R.P. (editor): Nitrogen Dioxide. Sittig's Handbook of Toxic and Hazardous Chemicals and Carcinogens, Fourth Ed., Vol. 2. Norwich, NY: Noyes Publications, William Andrew Publishing, 2002, pp. 1691-1694.
Zeidler, P.C. and Castranova, V: Role of nitric oxide in pathological responses of the lung to exposure to environmental/occupational agents. Redox. Rep. 9(1): 7-18, 2004.

Last Updated Date : 01/28/2021

Lapse in Appropriations

NITRIC OXIDE†

Chemical Identification

Physical Properties

Monitoring Methods Used by OSHA

Bulk/Wipe Method

On-Site Screening Techniques

Exposure Limits

Additional Resources and Literature References