Material Safety Data Sheet (MSDS) – Stannous Oxide

Identification

Product Name: Stannous Oxide
Chemical Formula: SnO
Synonyms: Tin(II) oxide, tin monoxide
CAS Number: 21651-19-4
Use: Widely applied in glass manufacturing, ceramics, and as a reducing agent in chemical processes.
Manufacturer Information: Be sure to contact the supplier or manufacturer directly for detailed batch or regional specifics.
Emergency Contact: Refer to the package or supplier documentation for regional emergency phone numbers.

Hazard Identification

Classification: Considered hazardous under OSHA Hazard Communication Standard.
Physical Hazards: Fine powder poses risk of dust explosion; not flammable, but dust can form explosive mixtures in air.
Health Hazards: Inhalation and skin contact may cause irritation; dust exposure could lead to respiratory discomfort over time.
Environmental Hazards: Toxic to aquatic organisms in significant concentrations; avoid large releases into soil or waterways.
Signal Word: Warning
Label Elements: Exclamation mark, Environmental hazard symbol
Potential Effects: Coughing, shortness of breath, possible mild dermatitis upon skin contact, possible eye irritation.

Composition / Information on Ingredients

Chemical Name: Stannous Oxide
Common Name: Tin monoxide
CAS Number: 21651-19-4
Concentration: 98-100% by weight
Impurities: Trace amounts of other tin oxides, metallic tin

First Aid Measures

Inhalation: Move affected person to fresh air without delay; give oxygen only if breathing becomes difficult; seek medical attention for prolonged symptoms.
Skin Contact: Remove contaminated clothing; wash exposed skin with soap and plenty of running water; medical advice recommended if irritation continues.
Eye Contact: Rinse eyes with plenty of water, keeping eyelids open; remove contact lenses gently; consult an eye specialist if discomfort remains.
Ingestion: Rinse mouth thoroughly with water; do not induce vomiting; medical evaluation is important for accidental swallowing or if symptoms show up.
Most Important Effects: Dust exposure can irritate airways and cause discomfort; long-term effects unlikely under normal industrial conditions if controls are followed.

Fire-Fighting Measures

Suitable Extinguishing Media: Use dry sand, dry chemical, or carbon dioxide; water spray is suitable only for small fires.
Unsuitable Media: Avoid direct, strong water streams on bulk powder as material may react.
Hazardous Combustion Products: Tin fumes and oxides may form during combustion.
Protective Equipment for Firefighters: Standard firefighting gear with self-contained breathing apparatus, as tin dust or fumes generated at high heat can be harmful.
Fire and Explosion Hazards: Dust can accumulate and form potentially explosive mixtures with air, particularly if dispersed in confined spaces.

Accidental Release Measures

Personal Precautions: Avoid dust formation and inhalation; ventilate closed areas; wear respirator and protective gear.
Environmental Precautions: Prevent further spillage; avoid run-off to drains and natural water streams.
Clean-up Methods: Use non-sparking tools for collection; sweep up and shovel; place in closed, labeled containers for disposal or reuse; wash area with plenty of water.
Emergency Procedures: Isolate the hazard area; evacuate unnecessary personnel; restrict entry to qualified clean-up crews only.

Handling and Storage

Handling: Only handle in well-ventilated areas; control dust at source; avoid prolonged or repeated exposure; avoid releasing dust into the air; wear recommended personal protection.
Storage: Store in tightly closed containers; keep in dry, cool places away from strong acids, oxidizers, and foodstuffs.
Storage Conditions: Recommended temperature: ambient; keep away from moisture and water; store away from incompatible substances.
Incompatible Materials: Strong oxidizing agents, acids.

Exposure Controls and Personal Protection

Occupational Exposure Limits: OSHA PEL for tin compounds (as Sn): 2 mg/m³ (TWA); ACGIH TLV: 2 mg/m³ (TWA).
Engineering Controls: Use local exhaust ventilation, process enclosure or other engineering controls to maintain airborne dust below recommended limits.
Protective Equipment: Respiratory protection may be necessary if dust levels exceed limits; safety goggles; chemical-resistant gloves; lab coat or appropriate work clothing.
Hygiene Measures: Wash hands and face before eating, drinking, or smoking; keep work clothes separate from street clothes.

Physical and Chemical Properties

Appearance: Greenish-yellow to brownish-black solid powder; fine, odorless.
Odor: Odorless
Odor Threshold: Not applicable
pH: Not applicable (insoluble in water)
Melting Point/Freezing Point: 1080°C
Boiling Point: Decomposes before boiling
Flash Point: Not flammable
Evaporation Rate: Not applicable
Flammability: Not flammable, but dust may be combustible
Vapor Pressure: Not applicable
Vapor Density: Not applicable
Specific Gravity: 6.45 (water = 1)
Solubility: Insoluble in water; soluble in strong acids
Partition Coefficient (n-octanol/water): Not determined
Auto-ignition Temperature: Not applicable
Decomposition Temperature: >1500°C
Viscosity: Not applicable

Stability and Reactivity

Chemical Stability: Stable under normal conditions; exposed powders may oxidize to tin dioxide
Reactivity: Stable with most materials under normal conditions
Hazardous Reactions: Can react with strong oxidizing agents, strong acids; may generate heat or gas in violent reactions
Conditions to Avoid: Avoid strong heat, moisture, formation of dust clouds
Incompatible Materials: Avoid mixing with oxidizers, acids, or bases that could trigger exothermic reactions
Hazardous Decomposition Products: Tin oxides

Toxicological Information

Acute Toxicity: Low oral and inhalation toxicity expected from animal studies; no significant acute hazard with normal industrial exposure.
Skin Corrosion/Irritation: Can cause mild to moderate skin irritation on prolonged contact.
Eye Damage/Irritation: Dust may irritate eyes; redness, tearing, and mild discomfort described in case reports.
Respiratory Sensitization: No evidence for asthma or allergic-type responses with occupational levels.
Chronic Toxicity: Long-term exposure to tin compounds linked with mild pneumoconiosis but not life-threatening lung disease.
Carcinogenicity: Not listed as a carcinogen (IARC, NTP, OSHA).
Mutagenicity/Reproductive Effects: No data show genetic or reproductive hazard at typical exposure levels.

Ecological Information

Ecotoxicity: Toxic to aquatic life; hazard increases in high concentrations; stannous ion can disrupt normal biological processes in fish and invertebrates.
Persistence and Degradability: Not biodegradable; persists in soils and sediments.
Bioaccumulation Potential: Low; tin does not significantly accumulate in animal tissues.
Mobility in Soil: Limited; tends to remain in particulate form and bind to sediments
Other Adverse Effects: Large discharges can harm aquatic habitats; avoid release into natural environment.

Disposal Considerations

Disposal Methods: Collect waste material in suitable, labeled containers; follow local, regional, and national regulations for disposal.
Contaminated Packaging: Rinse containers before recycling or disposal; handle packaging as chemical waste if contaminated.
Special Precautions: Do not dump to surface water, sewer, or soil; consult local waste authorities for direction.

Transport Information

UN Number: Not regulated by UN as a hazardous material for transport.
Transport Hazard Class: Non-hazardous according to most international regulations.
Packing Group: Not assigned
Environmental Hazards: Not a marine pollutant in small quantities; use care for bulk shipments.
Special Transport Precautions: Package securely in dust-tight, labeled containers; minimize breakage or spillage during transit.
Regulatory Transport Notes: Review all packaging and labeling needs before shipping internationally.

Regulatory Information

OSHA: Covered under Hazard Communication Standard; requires labeling and SDS at point of industrial use.
EPA: May be subject to reporting under SARA Title III, CERCLA if large releases occur.
TSCA: Listed on the US Toxic Substances Control Act inventory.
REACH: Registered in the EU; classified for environmental and health hazards.
Other Standards: Check updated listings in country-specific regulations such as WHMIS, GHS, and the Australian Inventory.
Label Information: Always mark containers with product name, hazard signage, precautionary statements, and supplier identification.