Tungsten Hexafluoride (WF₆) Material Safety Data Sheet (MSDS)

Identification

Product Name: Tungsten Hexafluoride
Chemical Formula: WF₆
Synonyms: Tungsten(VI) fluoride
CAS Number: 7783-82-6
Recommended Use: Semiconductor manufacturing, chemical vapor deposition
Manufacturer: Industry supplier information required
Contact Information: Hazard response phone numbers vary by region
Emergency Phone: Use country-appropriate emergency services
REACH Registration Number: Required if applicable in your country
Date Prepared: Always check label or supplier’s documentation for the most current information

Hazard Identification

Classification (GHS): Acute toxicity (inhalation) category 2, Skin corrosion category 1A, Specific target organ toxicity (single exposure) category 3
Hazard Statements: Causes severe burns to skin and eyes, toxic if inhaled, may cause respiratory irritation or distress
Signal Word: Danger
Pictogram: GHS05 (Corrosive), GHS06 (Toxic), GHS07 (Exclamation mark)
Precautionary Statements: Keep container tightly closed, avoid all contact with skin and eyes, use only outdoors or in a well-ventilated area, avoid breathing vapor
Routes of Exposure: Inhalation, skin contact, eye contact
Target Organs: Lungs, eyes, skin, mucous membranes
Symptoms: Burning sensation in respiratory tract, choking, skin and eye burns, cough, pulmonary edema risk
NFPA Ratings: Health: 4; Flammability: 0; Reactivity: 2

Composition / Information on Ingredients

Chemical Name: Tungsten Hexafluoride
CAS Number: 7783-82-6
Concentration: 100% (pure product)
Other Ingredients: None expected in standard cylinders; product is sold as a high-purity gas for use in industrial and laboratory settings
Impurities: Trace contaminants possible, check manufacturer’s specification sheet

First Aid Measures

Inhalation: Remove exposed person to fresh air immediately, call emergency medical services at once, maintain open airway, give oxygen by qualified personnel, expect pulmonary complications—even delayed onset
Skin Contact: Remove contaminated clothing and rinse affected area with copious amounts of water for at least 15 minutes, do not rub skin, call physician or poison center without delay
Eye Contact: Rinse eyes under running water for at least 15 minutes, lift upper and lower eyelids occasionally, seek emergency care immediately
Ingestion: Unlikely route—product is a gas, but in case of accidental oral exposure, do not induce vomiting, rinse mouth, and get medical attention fast
Special Notes: Symptoms may arise after delay—observe exposed person closely; always have safety showers and eyewash stations ready in areas using this chemical

Fire-Fighting Measures

Suitable Extinguishing Media: Use water spray, fog, alcohol-resistant foam on surrounding fire, but direct water streams may increase hydrofluoric acid formation
Unsuitable Media: Carbon dioxide, dry chemical extinguishers ineffective
Specific Hazards: Decomposes in contact with moisture or heat to release hydrogen fluoride and other toxic fumes
Protective Equipment: Full face self-contained breathing apparatus (SCBA), chemical-protective clothing in positive pressure mode
Special Fire-Fighting Procedures: Evacuate area, control leaks at source if safely possible, keep storage cylinders cool with water spray from safe distance, stay upwind, block off drains to stop runoff contamination
Combustion Products: Tungsten oxides, hydrogen fluoride (extremely hazardous and corrosive)

Accidental Release Measures

Personal Precautions: Evacuate area immediately, call trained hazardous materials response, wear self-contained respirator and impervious clothing
Environmental Precautions: Prevent entry to sewers, surface water, or soil
Containment Procedures: Stop leak if safe, ventilate enclosed spaces with explosion-proof fans, dilute with water fog—be aware this forms sprays of hydrofluoric acid
Cleanup Methods: Trained personnel use appropriate gas detectors, fix leaks using compatible materials, neutralize residue with lime or soda ash slurry, always test area for residual hazards before reentry
Disposal: Collect waste material in corrosion-resistant, vented containers for disposal per local regulations
Notification: Inform authorities immediately if large releases pose public or environmental threat

Handling and Storage

Safe Handling: Always use in fully vented fume hood or gas cabinet with local vapor scrubbers, wear suitable PPE at all times, never breathe fumes or allow direct contact with skin, perform leak checks regularly
Storage Conditions: Store cylinders upright and secure to prevent falling, keep in cool, dry, well-ventilated space away from moisture and incompatible chemicals, protect from mechanical damage, avoid corrosive or damp storage areas
Incompatible Materials: Strong bases, acids, alkalis, water, moisture, glass, ceramics, metals that can be attacked by HF
Special Requirements: Clearly label all containers, keep access restricted to trained personnel, check cylinder valves and safety relief devices regularly for leaks

Exposure Controls and Personal Protection

Occupational Exposure Limits: ACGIH TLV (as hydrogen fluoride): 0.5 ppm ceiling, NIOSH REL: 2.5 mg/m³ ceiling
Engineering Controls: Use only in certified, mechanically ventilated enclosures or process systems, gas detection systems with local and remote alarms highly recommended
Respiratory Protection: Positive pressure air-supplied respirators required during any possibility of exposure, escape-type respirators to be available nearby
Skin Protection: Chemical-resistant gloves (Viton or similar), full-length acid-resistant suits, boots
Eye Protection: Tight-fitting chemical splash goggles with full face shield
Work Hygiene: Wash thoroughly after handling, always remove contaminated clothing and rinse it before reuse, keep food and drink away from work areas
Monitoring: Continuous area and personal monitoring for fluoride ions recommended

Physical and Chemical Properties

Appearance: Colorless to pale yellow gas at room temperature
Odor: Pungent, irritating (sharp stinging odor similar to hydrogen fluoride)
Molecular Weight: 297.83 g/mol
Boiling Point: 17.1°C (62.8°F)
Melting Point: -2.1°C (28.2°F)
Vapor Pressure: 1 atm @ 17°C
Solubility: Reacts violently with water, forms hydrofluoric acid and tungstic acid
Density: 3.44 g/L (gas at 0°C, 1 atm)
Vapor Density (air = 1): 10.3
Flammability: Not flammable
Other Properties: Strong oxidizer, highly corrosive to many metals and tissue, reacts exothermically with water

Stability and Reactivity

Chemical Stability: Stable in sealed containers under inert, dry atmospheres
Reactivity: Forms hazardous products on contact with water, alcohols, organic materials, strong bases
Conditions to Avoid: Moisture, heat, incompatible substances, exposure to air
Incompatible Materials: Water, strong acids, alkalis, reacting metals, glass, ceramics, many plastics
Hazardous Decomposition Products: Hydrogen fluoride, tungsten oxides, additional toxic and corrosive fumes that may be released on heating or burning
Polymerization: Will not occur under normal recommended conditions, but hazardous decomposition possible

Toxicological Information

Acute Toxicity: LC₅₀ (inhalation, rat): 0.6 ppm/1h (extremely toxic by inhalation)
Skin Corrosion/Irritation: Causes severe burns and tissue destruction
Eye Damage/Irritation: Severe irreversible tissue destruction
Sensitization: Not expected to cause allergy
Chronic Effects: Prolonged or repeated exposure affects bones and teeth due to fluoride ions, may cause systemic toxicity through inhalation
Carcinogenicity: Not classified as a carcinogen by IARC, NTP, OSHA
Mutagenicity: No reliable evidence for mutagenic effects
Target Organs: Respiratory system, skin, eyes, teeth, bones
Symptoms of Exposure: Burning pain, tissue sloughing, cough, choking, delayed lung injury

Ecological Information

Eco-toxicity: Highly toxic to aquatic and terrestrial life forms, hazard increases due to release of hydrofluoric acid
Persistence and Degradability: Non-biodegradable Bioaccumulative Potential: No information on bioaccumulation, but product expected to degrade quickly to fluoride
Mobility in Soil: Mobile as fluoride ion, especially in moist or acidic soils
Other Adverse Effects: Acidification risk for watercourses, danger to aquatic organisms from fluoride release
Precautions: Prevent uncontrolled discharge to environment

Disposal Considerations

Container Disposal: Empty gas cylinders must be purged and returned to supplier for reuse or recycling, never incinerate or landfill
Waste Disposal: Collect residues, neutralize with lime or soda ash in well-ventilated areas, manage wastes as hazardous according to regulatory codes
Regulatory Requirements: Comply with all national, state, and local hazardous waste regulations, notify authorities of any significant quantities of release or spillage
Precautions for Disposal: Avoid contact with water or strong acids during collection and transport

Transport Information

UN Number: 2196
Proper Shipping Name: Tungsten hexafluoride, compressed
Hazard Class: 2.3 (Toxic gas)
Packing Group: Not applicable, toxic gas classification
Label Requirements: Toxic Gas, Corrosive
Marine Pollutant: No specific designation, but ecological risk from fluoride release is serious
Special Transport Precautions: Only trained personnel may load and unload cylinders, always inspect packages for leaks, store upright and secure during transport, local and international rules differ, always double-check before shipment
Emergency Response Guide: ERG Guide 124 for toxic compressed gases

Regulatory Information

Workplace Classification: OSHA highly hazardous chemical (29 CFR 1910.119), covered under EPA Toxic Substances Control Act (TSCA), hazardous by EU CLP/GHS
Inventory Status: Listed on TSCA, REACH, EINECS/ELINCS as appropriate
SARA Title III: Not a Section 302 extremely hazardous substance, Section 313 reportable
State Regulations: Subject to state right-to-know regulations; listed in California Proposition 65
Other International Regulations: Check applicable national chemical control laws
Labelling Requirements: GHS label requirements: hazard pictograms, signal words, hazard statements, precautionary statements must all appear clearly on packaging
Restrictions on Use: Use restricted to trained, authorized personnel with engineering controls and PPE in place