Product Name: Helium Acetonitrile
Chemical Formula: Mixture of Helium (He) and Acetonitrile (CH₃CN)
Recommended Use: Industrial gas blends, laboratory research, chemical syntheses
CAS Numbers: Helium (7440-59-7), Acetonitrile (75-05-8)
Manufacturer: Standard supplier details on packaging
Emergency Contact: Local poison control or fire department
Helium: Simple asphyxiant, displaces oxygen in enclosed areas, can lead to suffocation without warning
Acetonitrile: Highly flammable liquid and vapor, toxic if swallowed or inhaled, causes skin and eye irritation, risk of toxic hydrogen cyanide on combustion or metabolic breakdown
Primary Routes of Entry: Inhalation, skin contact, eye contact, ingestion
GHS Classification: Flammable liquids (Category 2), acute toxicity (oral and inhalation), skin/eye irritant, aspiration hazard
Helium: 10-95% by volume, inert noble gas
Acetonitrile: 5-90% by volume, colorless flammable liquid
Impurities: Trace moisture and hydrocarbons may be present
Mixture Nature: Not chemically reactive under normal conditions; physical blend of compressed gas and volatile solvent
Inhalation: Move person to fresh air, avoid self-exposure, administer oxygen if breathing is difficult, seek immediate medical attention if symptoms persist
Skin Contact: Remove contaminated clothing, rinse skin with soap and water for several minutes, seek medical advice if irritation develops or persists
Eye Contact: Flush eyes with plenty of water for at least 15 minutes keeping eyelids open, remove contact lenses if present and easy, seek immediate medical care
Ingestion: Do not induce vomiting, rinse mouth, seek urgent medical attention, monitor for symptoms of poisoning such as headache, confusion, or shortness of breath
Suitable Extinguishing Media: Dry chemical, CO2, alcohol-resistant foam, do not use water directly on the chemical as it can spread flammable vapors
Specific Hazards: Acetonitrile can form toxic gases on decomposition (hydrogen cyanide, nitrogen oxides, carbon monoxide)
Protective Equipment: Full protective gear, self-contained breathing apparatus recommended for firefighters
Special Precautions: Approach fire from upwind, keep containers cool with water spray, evacuate area if large volumes involved
Personal Precautions: Evacuate non-essential personnel, ventilate area, avoid inhaling vapors or direct contact, use appropriate respiratory and skin protection
Environmental Precautions: Prevent entry into drains, watercourses, and soil; contact authorities in large spill scenario
Methods for Containment: Stop leak if safe, use non-sparking tools, dike and absorb with inert material like sand or vermiculite, collect in proper containers for disposal
Cleanup Procedures: Dispose of residues according to regulations, decontaminate area with soap and water
Handling: Use in well-ventilated areas, avoid sources of ignition, ground all equipment, avoid breathing vapors, wear appropriate PPE
Storage Conditions: Store in tightly closed containers, in dry, cool, well-ventilated locations, away from heat, sparks, open flame, incompatible chemicals such as strong acids and bases
Special Considerations: Segregate from oxidizers and reactive substances, do not use plastic piping for transfer of pressurized gas, inspect cylinders regularly for leaks or damage
Occupational Exposure Limits: Helium (asphyxiant, not assigned), Acetonitrile (50 ppm TWA, 60 ppm STEL OSHA/ACGIH)
Engineering Controls: Local exhaust ventilation, use of explosion-proof electrical fixtures
Personal Protective Equipment: Chemical-resistant gloves (nitrile or PVC), safety goggles or face shield, flame-resistant protective clothing, respiratory protection for high concentrations or poorly ventilated areas (half-mask or full-face air-purifying respirator fitted with organic vapor cartridges)
Hygiene Recommendations: Wash hands after handling, do not eat, drink, or smoke in work areas, launder contaminated clothing before reuse
State: Pressurized gas-liquid mixture
Color: Colorless
Odor: Ether-like, mildly sweet (acetonitrile component)
Boiling Point: Acetonitrile: 81.6°C (179°F)
Melting Point: Acetonitrile: -45°C (-49°F)
Density: Acetonitrile: 0.786 g/cm³, Helium: 0.1786 g/L (at STP)
Solubility: Acetonitrile miscible in water, Helium slightly soluble
Vapor Pressure: High
Flammability: Acetonitrile is highly flammable; mixture forms explosive atmospheres with air
pH: Not applicable (neutral gas and solvent)
Chemical Stability: Stable under recommended storage and handling conditions, not easily polymerized
Incompatible Materials: Strong oxidizing agents, acids, bases, alkali metals, halogens
Hazardous Decomposition: Toxic gases (hydrogen cyanide, nitrogen oxides, carbon monoxide) can form under fire or thermal breakdown
Reactivity: Pressurized containers may rupture if heated, acetonitrile vapor can form explosive mixtures with air
Routes of Exposure: Inhalation (primary), skin/eye contact, ingestion
Target Organs: Central nervous system, liver, respiratory tract
Symptoms: Headache, dizziness, nausea, confusion, drowsiness, shortness of breath; larger exposures cause cyanosis, convulsions, death
Acute Toxicity: Acetonitrile oral LD50 (rat): 2730 mg/kg, inhalation LC50 (rat, 4h): 7551 ppm
Chronic Exposure: Long-term skin or inhalation exposure may affect liver and kidney function
Carcinogenicity: Not classified by IARC as carcinogenic, but long-term exposure should be minimized
Aquatic Toxicity: Acetonitrile is toxic to aquatic organisms at high concentrations
Persistence and Degradability: Degrades in air by photochemical reactions, moderate degradation in water and soil
Bioaccumulation Potential: Low, acetonitrile does not significantly accumulate in aquatic organisms
Mobility in Soil: High, can migrate to groundwater
Helium: Not considered an environmental hazard due to inertness and atmospheric dilution
Waste Disposal: Consult local, state, and federal environmental authorities before disposal; burnt in a chemical incinerator equipped with scrubber and afterburner; do not dispose of via drains
Contaminated Packaging: Empty containers carry product residue (vapor, liquid), follow safe disposal as hazardous waste
Precautions: Do not attempt to vent or puncture pressurized containers unsafely, ventilate residual gases before recycling or disposal
UN Number: UN 1648 (Acetonitrile), UN 1046 (Helium, compressed)
Hazard Class: 3 (Flammable liquid)/2 (Non-flammable gas)
Packing Group: II for acetonitrile
DOT Labeling: Flammable liquid and non-flammable gas labels
Special Transport Notes: Secure cylinders for transport, keep away from heat, transport vehicles must be adequately ventilated to prevent accumulation of toxic or explosive vapors
OSHA: Acetonitrile listed as hazardous, subject to workplace standards and monitoring
EPA: Acetonitrile classified as hazardous waste (RCRA D001, D003, F-listed)
TSCA: Both components listed
SARA Title III: Acetonitrile is a listed hazardous substance for emergency planning and community right-to-know
International Regulations: Acetonitrile included in EU REACH, carries risk and safety phrases relating to flammability, health hazards, and environmental hazards
