NIOSH Publication No. 2005-151:

NIOSH Pocket Guide to Chemical Hazards

September 2005

Sodium bisulfite

CAS
7631-90-5

NaHSO3

RTECS
VZ2000000
Synonyms & Trade Names

Monosodium salt of sulfurous acid, Sodium acid bisulfite, Sodium bisulphite, Sodium hydrogen sulfite
DOT ID & Guide
2693 / 154 (solution)

Exposure
Limits

NIOSH REL: TWA 5 mg/m3
OSHA PEL†: none
IDLH
N.D. See: IDLH INDEX
Conversion
Physical Description
White crystals or powder with a slight odor of sulfur dioxide.
MW: 104.1
BP: Decomposes
MLT: Decomposes
Sol: 29%
VP: ?
IP: NA

Sp.Gr: 1.48
Fl.P: NA
UEL: NA
LEL: NA

Noncombustible Solid
Incompatibilities & Reactivities

Heat (decomposes) [Note: Slowly oxidized to the sulfate on exposure to air.]
Measurement Methods
NIOSH 0500
See: NMAM or OSHA Methods
Personal Protection & Sanitation
(See protection)
Skin: No recommendation
Eyes: No recommendation
Wash skin: No recommendation
Remove: No recommendation
Change: No recommendation

First Aid
(See procedures)
Eye: Irrigate immediately

Breathing: Fresh air
Swallow: Medical attention immediately
Respirator Recommendations
Not available.
Important additional information about respirator selection
Exposure Routes
inhalation, ingestion, skin and/or eye contact
Symptoms
Irritation eyes, skin, mucous membrane
Target Organs
Eyes, skin, respiratory system
See also: INTRODUCTION