Product Identification

Product Name

Sodium hyposulfite

Synonyms

Chlorine Control
Chlorine Cure
Declor-It
Disodium thiosulfate
S-Hydril
Sodium hyposulfite

CAS

7772-98-7

Formula

Na2O3S2

Molecular Weight

158.09

EINECS

231-867-5

RTECS

XN6476000

RTECS Class

Other

Merck

12,8844

Beilstein/Gmelin

12718 (G)

Physical and Chemical Properties

Appearance

White, odorless powder.

Solubility in water

500 g/L

Melting Point

48

Boiling Point

100

Density

1.66 g/cm3

Usage

To remove chlorine from solution, as antichlor in bleaching of paper pulp, fixer in photography, mordant in dyeing & printing textiles, reducer in chrome dyeing, manufacture leather, extracting of silver from ores, bleaching bone, straw, ivory, reagent in analytical chemistry, antidote (cyanide poisoning).

First Aid Measures

Ingestion

If victim is conscious and alert, give 2-4 cupfuls of milk or water. Get medical aid.

Inhalation

Remove from exposure to fresh air immediately. If not breathing, give artificial respiration. If breathing is difficult, give oxygen. Get medical aid if cough or other symptoms appear.

Skin

Flush skin with plenty of soap and water for at least 15 minutes while removing contaminated clothing and shoes. Get medical aid if irritation develops or persists.

Eyes

Flush eyes with plenty of water for at least 15 minutes, occasionally lifting the upper and lower eyelids. Get medical aid.

Handling and Storage

Storage

Store in a cool, dry, well-ventilated area away from incompatible substances. Keep away from strong acids.

Handling

Wash thoroughly after handling. Remove contaminated clothing and wash before reuse. Use with adequate ventilation. Minimize dust generation and accumulation. Avoid contact with skin and eyes. Keep container tightly closed. Avoid ingestion and inhalation.

Hazards Identification

Ingestion

Ingestion of large amounts may cause gastrointestinal irritation.

Inhalation

May cause respiratory tract irritation.

Skin

May cause skin irritation.

Eyes

May cause eye irritation and possible burns.

Exposure Controls/Personal Protection

Personal Protection

Eyes: Wear appropriate protective eyeglasses or chemical safety goggles as described by OSHA's eye and face protection regulations in 29 CFR 1910.133 or European Standard EN166. Skin: Wear appropriate protective gloves to prevent skin exposure. Clothing: Wear appropriate protective clothing to minimize contact with skin.

Respirators

Follow the OSHA respirator regulations found in 29CFR 1910.134 or European Standard EN 149. Always use a NIOSH or European Standard EN 149 approved respirator when necessary.

Fire Fighting Measures

Fire Fighting

Wear a self-contained breathing apparatus in pressure-demand, MSHA/NIOSH (approved or equivalent), and full protective gear. Dusts at sufficient concentrations can form explosive mixtures with air. Combustion generates toxic fumes. Extinguishing media: Use water spray, dry chemical, or carbon dioxide.

Accidental Release Measures

Small spills/leaks

Sweep up, then place into a suitable container for disposal. Avoid generating dusty conditions.

Stability and Reactivity

Incompatibilities

Sodium nitrite, strong acids, strong oxidizers, water reactive materials. Deliquescent in moist air. Efflorescent in warm dry air.

Stability

Stable under normal temperatures and pressures.

Decomposition

Oxides of sulfur, hydrogen sulfide, sodium oxide.