Chemical Name: Dimethylamine
Other Designations: DMA, Dimethylamine anhydrous
CAS Number: 124-40-3
Common Uses: Water treatment chemicals, agricultural intermediates, rubber processing, pharmaceuticals, flocculant production
Hazard Classification: Flammable gas (Category 1), Acute toxicity inhalation (Category 3), Skin irritation (Category 2), Eye irritation (Category 2A)
Physical Hazards: Forms explosive mixtures with air, leaks quickly due to low boiling point
Health Hazards: May irritate respiratory tract, causes severe eye discomfort, potential for skin burns, risk of pulmonary edema if inhaled at high concentrations
Symbols: Flame, exclamation mark, skull and crossbones
Main Concerns: Leakage poses both flammability and asphyxiation risk, uncertainty of chronic low-level exposure effects, need for dedicated ventilation and detection in confined areas
Chemical Composition: Dimethylamine (Minimum 99% by weight, balance may include trace water or methanol)
Impurities: Trace formaldehyde or methylamine result from process variability, impact typically <0.1%
Physical State: Compressed liquefied gas at room temperature, clear and colorless, sharp ammonia-like odor
Inhalation: Move exposed person to fresh air immediately, supply oxygen by mask if breathing is difficult, monitor for respiratory symptoms including cough, delayed lung effects possible
Skin Contact: Rinse affected area with large volumes of water, remove contaminated clothes, never use neutralizing agents directly on skin
Eye Contact: Flush eyes with water continuously for at least 15 minutes, seek medical attention due to the risk of vision impairment
Ingestion: Unlikely in gas phase, contact medical services urgently for any oral exposure
Notes for Doctors: Treat symptoms, monitor for delayed respiratory complications, avoid unnecessary movement until stable
Flammability: Ignites easily in air, forms explosive limits between 2.8% and 14.4% by volume in air
Extinguishing Media: Use carbon dioxide, dry powder, or foam agents, avoid water spray near live electrical installations
Special Procedures: Evacuate area due to vapor cloud explosion risk, keep containers cool with water fog, explosion risk for fire-exposed cylinders
Protective Equipment: Full protective gear including SCBA required, as combustion forms toxic gases such as nitrogen oxides
Hazards from Combustion: Exothermic reaction, rapid pressure buildup in unventilated spaces, failure to control temperature compounds emergency
Personal Precautions: Evacuate area, ventilate promptly, restrict ignition sources, wear approved chemical goggles and gloves, self-contained breathing apparatus in large spills
Environmental Risks: Highly soluble in water, risk of aquatic toxicity if large volumes escape containment
Clean-up Methods: Gas leaks dissipate rapidly; liquid releases collect with absorbent material, neutralize small spills with dilute acid under fume hood
Notification: Adhere to local reporting obligations, especially in proximity to drainage or open water bodies
Containment Equipment: Designated absorbents for base chemicals, vapor barriers for large releases
Handling: Use in explosion-proof environments, ground and bond equipment during transfer, avoid inhaling vapor, implement thorough leak-checking practices
Storage Conditions: Secure well-ventilated areas, keep away from incompatible materials including strong oxidizers and acids, tightly seal connections to minimize leaks
Temperature Control: Store below 40°C, keep shadowed from sunlight, cylinders upright and chained securely
Transfer Practices: Use metallic lines or approved hoses, check regularly for wear, fit pressure relief valves
Workplace Controls: Regular inspection and staff safety drills, continuous vapor monitoring in filling and bulk storage zones
Occupational Limits: ACGIH TLV set at 5 ppm (TWA), short-term exposure limit 15 ppm, compliance checked with direct-reading gas detectors
Engineering Controls: Forced ventilation in use zones, interlocked alarm systems for leaks, sealed systems with automatic cut-off valves
Personal Protective Equipment: Chemical-resistant gloves (butyl rubber or nitrile), safety goggles, flame-retardant coveralls, positive-pressure breathing apparatus for confined spaces
Hygiene Requirements: No smoking, eating, or drinking near operations, mandatory handwashing before and after routine handling
Environmental Controls: Dedicated scrubbers for off-gases, regular containment area integrity checks, backup power to emergency ventilation
Appearance: Colorless gas, sometimes compressed to a liquid
Odor: Strong ammonia-like, highly pungent
Boiling Point: 7°C
Melting Point: -93°C
Solubility: Highly soluble in water and alcohols
Vapor Pressure: Elevated at ambient temperature (approx. 2.1 bar at 20°C)
Density: Gas density lower than air, liquid phase around 0.67 g/cm³
pH in Solution: Strongly alkaline
Stability: Remains stable under recommended storage and operational conditions, significant hazard only arises if exposed to high heat, intense sunlight, or incompatible materials
Reactivity: Reagent with acids producing explosive vapors, oxidizes violently with chlorinated species, can cause corrosion of non-nickel piping due to base strength
Avoid: Acidic substances, hypochlorite cleaners, oxidizers, copper alloys
Decomposition Products: Nitrogen oxides, methylamine, formaldehyde under severe heating
Polymerization: Does not self-polymerize, main risk remains uncontrolled exothermic reaction with strong acids
Routes of Exposure: Inhalation carries the most direct hazard, followed by skin and eye contact
Acute Toxicity: Respiratory irritation at exposures as low as 5 ppm, acute health effects possible above 100 ppm, LC50 values (inhalation, rat) around 4500 ppm/4hr
Skin and Eye Contact: Severe irritation and burns, prolonged effects possible including corneal damage
Sensitization: Not commonly reported, but high vapor concentrations may exacerbate asthma or bronchitis
Chronic Effects: No definitive evidence for cancer risk in humans, repeated exposure leads to chronic airway irritation and cutaneous effects
Environmental Distribution: Spills dissolve quickly in water, forming methylamine and ammonium compounds downstream
Aquatic Toxicity: LC50 for freshwater fish (96 hr) 100-250 mg/L, rapid oxygen depletion can occur in large spills
Biodegradability: Microbial breakdown in soil and water is efficient, risk remains with high-concentration discharges
Bioaccumulation: Unlikely due to rapid breakdown and mobility, no significant risk of food chain build-up
Regulatory Observations: Discharges in sensitive areas prompt regulatory reporting and remediation
Waste Characterization: Residues classified as hazardous, avoid pouring into drains or open soil
Treatment Methods: Prefer incineration in chemical waste system equipped with acid scrubber, dedicated neutralization systems for dilute solutions
Regulatory Aspects: Disposal must comply with regional and national regulations for hazardous chemical waste, manifests maintained for traceability
Reusable Packaging: Certified returnable gas cylinders, requiring decontamination before refilling, single-use containers isolated and destroyed
UN Number: 1032
Proper Shipping Name: Dimethylamine, anhydrous
Hazard Class: 2.1 (Flammable Gas)
Packing Group: Not assigned (gas)
Transport Condition: Secure upright, properly labeled, segregate from oxidizers and acids
Vehicle Recommendations: Closed vehicles, temperature controls for long distances, regular compliance checks before leaving site
International Listings: Listed or restricted under REACH, US TSCA, Canadian DSL, and Japanese ENCS
Domestic Regulations: Air emission subject to environmental permitting, workplace exposure covered by labor safety codes
Labeling Responsibilities: Include correct hazard codes, precautionary statements, and emergency procedures
Operating License: Storage and use require approved permits, subject to regular inspection
Community Right-to-Know: Information made available to local responders, authorities, and surrounding communities in accordance with chemical safety laws
