SODIUM METABISULFITE

Chemical Identification
Chemical Identification
CAS # 7681-57-4; 7757-74-6
Formula

H₂O₅S₂.₂Na

Synonyms

disodium pyrosulfite; sodium metabisulphite; sodium pyrosulfite

Physical Properties
Physical Properties
Physical description White to yellowish crystals or powder with a slight odor of sulfur.
Boiling point decomposes Molecular weight 190.1
Freezing point/melting point >302°F (decomposes) Vapor pressure
Flash point Vapor density
Specific gravity 1.4 Ionization potential
Lower explosive limit (LEL) Upper explosive limit (UEL)
NFPA health rating NFPA fire rating
NFPA reactivity rating 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.) S112
Sampling group
Sampler/Sampling media Pre-assembled cassette with mixed cellulose ester filter (MCEF) 0.8 micron (25 or 37 mm) [MAWP025A0 or MAWP037A0]
Sampling time*

240-480 min

Sampling volume (TWA)*

480-960 L

Sampling flow rate (TWA)*

2 L/min

Sampling volume (STEL/Peak/C)*
Sampling flow rate (STEL/Peak/C)*
Analytical method instruments AAS/AES
Method reference OSHA ID-121 (fully validated)
Notes

Results will be reported from the elemental analysis for the element only; the stated identity of the actual sample contents is based on the assumption that the material sampled is as identified by the compliance officer using available documentation of materials and processes.

An elemental result provided may be converted to the desired compound by multiplying the result by the appropriate stoichiometric factor. A 91B report specific to the compound (including the stoichiometric conversion) may by be provided upon request by contacting the laboratory. The stoichiometric factor for sodium metabisulfite from sodium is 4.135.

Analysis for this analyte is based on water solubility.

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
Model/Type
Sampling information
(see manufacturer instructions)
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 REL-TWA

5 mg/m³

TLV-TWA

5 mg/m³ [1992]

PEL-TWA

5 mg/m³

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

NA

Skin notation

N

Skin notation

N

Skin notation

N

Notes:

Not established

Notes: Notes: Notes:
Health factors:  See NIH-NLM PubChem. IDLH
Carcinogenic classifications: TLV-A4 Notes:
AIHA emergency response planning guidelines - ERPG-1/ERPG-2/ERPG-3:
Additional Resources and Literature References
Additional Resources and Literature References

NOAA: CAMEO Chemicals - Sodium metabisulfite

NIOSH: Pocket Guide to Chemical Hazards - Sodium metabisulfite

Literature References

  • ACGIH: Documentation of the Threshold Limit Values (TLVs) and Biological Exposure Indices (BEIs) - Sodium metabisulfite. See annual publication for most recent information.

Last Updated Date : 01/12/2021