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Chemical Name: Methacrylic Acid
Chemical Formula: C4H6O2
Common Uses: Building block for polymers and resins, plays a role in adhesives, paints, and specialty plastics
Appearance: Clear or slightly yellow liquid with a sharp, acrid odor
Molecular Weight: 86.09 g/mol
CAS Number: 79-41-4
Odor Threshold: Detectable at low ppm levels, strong enough to notice leaks or spills quickly if one works with the acid regularly
Physical Hazards: Flammable liquid, vapor forms explosive mixtures with air, risk of bodily burns
Health Hazards: Causes skin burns and eye damage, inhalation irritates respiratory tract, harmful if swallowed, can sensitize skin and provoke allergic reactions with repeated exposure
Environmental Hazards: Acutely toxic to aquatic life, spillages harm water sources
Signal Word: Danger
Hazard Statements: Causes severe skin burns and eye damage, highly flammable liquid and vapor, may cause an allergic skin reaction with chronic contact, hazardous to aquatic environment
Main Ingredient: Methacrylic Acid (concentration usually above 99%)
Notable Impurities: Inhibitors such as Methoxyphenol (to prevent unwanted polymerization), trace acrylic acid
Relevant Chemical Families: Alpha, beta-unsaturated carboxylic acid group contributes to reactivity and hazardous profile
Eye Contact: Flush eyes with copious water for at least 15 minutes, remove contact lenses if present, medical attention needed
Skin Contact: Remove contaminated clothing, wash skin with plenty of soap and water, seek medical advice
Inhalation: Move person to fresh air, help breathing with oxygen if necessary, seek immediate medical help
Ingestion: Rinse mouth, do not induce vomiting, drink water if alert, call poison control and seek emergency medical intervention
Notes to Physician: Risk of chemical burns, treat symptomatically, refer to poisoning protocols for caustics
Suitable Extinguishing Media: Alcohol-resistant foam, dry chemical, carbon dioxide, water spray only for cooling tanks (never direct water jet)
Fire Hazards: Vapors heavier than air, spread along surfaces and ignite at distant points, decomposition gases may include toxic fumes such as carbon monoxide and acids
Protective Equipment: Firefighters use full-face self-contained breathing apparatus and chemical-resistant suits
Special Precautions: Approach from upwind, cool containers with water, remove sources of ignition, container rupture risk from built-up pressure
Personal Precautions: Evacuate area, ventilate enclosure, avoid skin or eye contact, wear chemical splash goggles, gloves, long sleeves, and respirators if needed
Environmental Precautions: Prevent entry into sewers, rivers, or soil, use dikes to contain spill
Cleanup Methods: Use inert absorbent such as sand or earth, collect without sparks, transfer to sealed containers, dispose of safely
Decontamination: Wash contaminated surface with plenty of water and detergent, neutralize residue if recommended by safety experts
Handling: Work in chemical fume hood or well-ventilated place, keep away from ignition sources and build-up of static electricity, avoid skin contact by wearing full protective gear, handle away from incompatible chemicals like oxidizers, bases, and acids
Storage: Store in tightly closed containers, keep cool and dry, separate from foodstuffs and incompatible materials, use inhibitors to prevent polymerization, monitor temperature and install explosion-proof electrical fittings in storage rooms
Advice for Workers: Familiarize themselves with emergency procedures, label containers clearly, never reuse packaging for food or drinks
Occupational Exposure Limits: Recommended ceiling and short-term exposure limits vary by local regulations, check values from trusted occupational health bodies
Engineering Controls: Use local exhaust ventilation, splash shields, emergency eyewash fountains and showers nearby
Personal Protective Equipment: Chemical-resistant gloves, goggles, face shield, flame-resistant coveralls, appropriate respirator for airborne vapor risk, rubber boots when cleaning spills
Hygiene Measures: Wash hands after handling, keep contaminated clothing away from common washing areas, never eat, drink, or smoke in places where the acid is used or stored
Physical State: Liquid
Color: Colorless to faint yellow
Odor: Pungent, acrid, unpleasant
pH: Acidic, about 1 (concentrated)
Boiling Point: Around 161°C (322°F)
Melting Point: 15°C (59°F)
Flash Point: 68°C (154°F) closed cup
Self-Accelerating Decomposition Temperature: Risk increases above 40°C, especially if uninhibited
Vapor Pressure: Moderate, vapor can irritate mucous membranes
Solubility: Miscible in water and many organic solvents
Density: About 1.02 g/cm³ at 20°C
Stability: Unstable if uninhibited or heated, forms dangerous polymer if not stabilized
Polymerization Risk: Strong tendency to polymerize suddenly and violently, especially under heat or contamination, stabilizers like methoxyphenol prevent runaways
Incompatible Materials: Avoid contact with strong oxidizing agents, strong acids, alkalis, and reducing agents, all of which trigger hazardous reactions
Decomposition Products: Carbon monoxide, carbon dioxide, irritating organic fumes
Safe Handling Practices: Keep temperature controlled, avoid all sources of heat or flame
Routes of Exposure: Eyes, skin, inhalation, ingestion
Acute Effects: Immediate pain and damage with skin or eye exposure, burns and ulcerations, cough and sore throat from inhaling fumes, possible distress if swallowed
Chronic Effects: Potential for sensitization, asthma-like symptoms, damage to mucous membranes with repeated low-dose exposure, skin dermatitis
Known Toxicity: LD50 (oral, rat) estimated at 1320 mg/kg, but severity varies by route and situation
Carcinogenicity: Not listed as carcinogenic by IARC, NTP, or OSHA
Key Facts for Workers: Extra caution for sensitized individuals or those with respiratory conditions
Acute Aquatic Toxicity: Demonstrates toxicity to aquatic organisms in low concentrations
Air & Water Mobility: Volatile, moves easily through soil when spilled, contaminates groundwater
Degradation: Degrades in the environment but intermediate products may still be harmful
Bioaccumulation: Not expected to bioaccumulate significantly, but spills lead to localized ecological stress
Impact Highlight: Even small accidental releases damage fish and invertebrates, necessitating strict control during use and transit
Safe Disposal: Incinerate under controlled conditions in professionally managed chemical incinerators
Waste Treatment Methods: Neutralize small amounts with sodium bicarbonate under a fume hood, employ secondary chemical treatment as necessary, major quantities go to hazardous waste facilities
Legal Compliance: Disposal must follow both local and national hazardous waste guidelines, never flush to drains, sewers, or natural bodies of water
UN Number: Recognized as a hazardous material for transportation by road, rail, sea, and air
Proper Shipping Name: Methacrylic Acid, Stabilized
Class: Flammable liquid
Packing Group: II (medium danger)
Special Precautions: Use only tightly sealed, chemical-resistant packaging, clearly label all containers, separate from food, feed, and unrelated chemicals during transit
Spill Response: Transporters trained in handling leaks, have spill kits and emergency plans ready
Workplace Safety: Substantial regulation covers use, storage, and disposal, including required training for handlers and mandatory safety labeling
Environmental Regulations: Controlled under clean air and water acts in many jurisdictions due to emission potential and aquatic toxicity
Occupational Limits: Referenced by agencies like OSHA, ACGIH, and similar groups worldwide for exposure controls
Consumer Restrictions: Not allowed for general consumer use, only trained professionals
SDS Update Requirements: Regulations require regular review and update of safety data, ensuring all workers stay informed about any changes in hazard status or recommended procedures
