Product name: Large-Granular Urea
Chemical formula: CH4N2O
Common use: Nitrogen fertilizer for agriculture
Physical form: White or slightly off-white granules, generally dry to the touch
Odor: Slightly ammoniacal, stronger when exposed to humidity or heat
Proper identification on packaging: “Urea, Granular, Nitrogen Fertilizer,” with recognized UN number for transport recognition where required
CAS Number: 57-13-6
Health hazards: Low acute oral, dermal, and inhalation toxicity, but can irritate eyes, skin, and respiratory tract on direct contact or heavy dust
Environmental hazards: High nitrogen content can cause eutrophication if it enters waterways
Fire hazards: Presents minimal fire risk, but thermal decomposition can release irritating gases like ammonia and small amounts of nitrogen oxides
Reactivity: Will react with strong oxidants and acids, creating potential for hazardous gases
Signal word: Not classified as hazardous under GHS, but practical vigilance is necessary given handling scale at industrial sites
Urea content: 98.5% or higher by weight
Moisture: Typically 0.3% or lower
Biuret: Often found at or below 1%
Trace impurities: Sometimes unreacted ammonia and small quantities of formaldehyde (as a stabilizer)
Additives: Anti-caking agents may be present in specific formulations, but overall composition remains dominated by urea itself
Eye contact: Flush eyes with clean, running water for at least fifteen minutes, keep lids open, seek attention if irritation persists
Skin contact: Wash exposed skin with soap and water—granules can cause dryness or mild irritation if left on skin for long periods; excess dust can worsen irritation
Inhalation: Move affected person to fresh air; loosen restrictive clothing, monitor for respiratory distress, and seek medical advice if symptoms are prolonged
Ingestion: Rinse mouth, give water to drink if person is fully conscious—seek medical help if large amounts are swallowed or persistent stomach upset occurs
General advice: Keep exposed team members under observation; do not delay professional care if eye or respiratory irritation is severe
Suitable extinguishing media: Water spray, dry powder, foam, or CO2 are effective as the compound itself is not highly combustible but packaging and additives could burn
Combustion products: Main risks relate to release of ammonia and small quantities of toxic nitrogen oxides in confined situations
Special equipment: Full protective clothing with suitable respiratory protection (self-contained breathing apparatus) in any significant fire
Precautions for fire-fighters: Approach from upwind, keep unnecessary personnel away, avoid runoff reaching drains or natural water sources
Unusual fire or explosion hazards: Urea can decompose at high temperatures above 133°C, producing ammonia gas, which clouds visibility and may irritate the respiratory tract
Personal protection: Use dust masks, chemical goggles, and gloves if bulk release occurs; avoid direct contact with eyes or prolonged contact with skin
Containment: Shovel or sweep up granules—avoid creating dust by handling gently, collect for reuse if possible or transfer to secure container for disposal
Environmental precautions: Prevent spillage from entering waterways or open drains; nitrogen runoff from urea can severely impact aquatic ecosystems
Clean-up methods: Wet sweeping or vacuum collection works best for minimizing airborne dust; thorough washing needed for contaminated surfaces; pay attention to invisible residues near drains or loading bays
Community safety: Alert nearby facilities if there’s a larger scale accidental release, especially if wind could blow dust toward populated or sensitive zones
Handling: Use local exhaust ventilation for bulk transfer, minimize dust generation, enforce glove and mask use in confined spaces
Storage: Keep in cool, dry, well-ventilated places—urea granules attract moisture, which can lead to caking and the release of ammonia; avoid storage near acids, nitrates, or oxidising agents
Pallet stacking: Do not overstack, allow for air circulation around sacks or silos; raised pallets or slatted floors help; avoid direct contact with ground or wet surfaces
Separation: Segregate from food and feed—cross-contamination with consumables must never occur
Maintenance: Clean spills promptly, rotate stock, monitor humidity closely to reduce lump formation over long-term storage
Ventilation: Use local exhaust or dust extraction systems in large-scale loading and blending zones
Respiratory protection: NIOSH-approved dust masks recommended for sustained exposure; higher level half-face respirators in enclosed or dusty environments
Eye and face protection: Non-vented chemical goggles or full face shield with heavy dust
Skin protection: Nitrile or PVC gloves prevent dryness and minor irritation; full coveralls in large-scale operations to minimize personal cleaning needs
Workplace limits: No specific occupational exposure limit for urea, but keep dust levels as low as possible for comfort and hygiene
Hygiene: Wash thoroughly before eating or drinking; avoid rubbing face or eyes with contaminated hands or gloves
Appearance: White, hard granules, occasionally with a slight sheen
Odor: Slight ammonia-like, generally only noticeable above ambient temperatures or if moisture begins to break down granules
Molecular weight: 60.06
Melting point: 132–135°C; above this, breakdown into ammonia and isocyanic acid begins
Solubility: Readily dissolves in water, exothermic reaction
Density (bulk): 0.72–0.78 g/cm3, varies with granule size and shape
pH of 10% solution: Slightly basic (pH 7.2–7.5)
Thermal stability: Granules remain stable at normal ambient temperatures but decompose rapidly above 130°C
Reactivity with acids: Strong acids trigger rapid decomposition, substantial ammonia release, and possible local heat buildup
Compatibility: Do not mix with strong oxidizers (nitric acid, chlorine compounds), as they dramatically increase fire and explosion risk
Decomposition products: Ammonia, CO2, small amounts of isocyanic acid and nitrogen oxides under high heat or fire
Storage lifespan: Remains chemically stable for months if protected from moisture and heat, but long exposure to humidity reduces particle strength, increases caking, and raises ammonia vapor risk
Acute toxicity: Oral and dermal toxicity are low in mammals; ingestion in small accidental quantities rarely causes symptoms, but large doses trigger gastrointestinal discomfort
Irritation: Dust causes mild eye and respiratory irritation; skin dryness or redness possible after repeated handling without gloves
Sensitization: Not a skin sensitizer;
Repeated exposure: No cumulative toxicity in typical workplace conditions, but unnecessary, repeated inhalation of urea dust should be avoided
Long-term risk: No evidence for carcinogenicity, mutagenicity, or reproductive harm in humans from urea alone, based on decades of agricultural use and toxicological testing
Aquatic toxicity: Urea is not toxic to fish or aquatic wildlife directly, but its nitrogen content causes algal blooms and oxygen depletion in waterways
Persistence: Completely soluble in water, so quickly disperses if released; excess buildup in soil can change nitrogen cycling and lower soil health over time
Bioaccumulation: Urea does not bioaccumulate, converts to ammonia and nitrate by soil bacteria
Effect on plants: Correct application supports strong plant growth, but direct overspill burns sensitive crops and increases risk of runoff
Reuse: Reclaim spilled, uncontaminated granules for repeat use whenever feasible
Disposal of waste: Do not pour into drains or water sources; incinerate or send to landfill in compliance with local, regional, and national rules for nitrogenous waste
Container cleaning: Empty bags or containers should be shaken or rinsed thoroughly before recycling or disposal
Regulations: Many countries require nitrogen fertilizer waste to be tracked, extra care in environmentally sensitive areas—contact environmental authority for local guidance
Avoiding problems: Limit product loss by regular equipment maintenance and keeping dust collection systems in good working condition
UN number: Urea commonly classified as non-hazardous for land and ocean shipping unless mixed with hazardous additives
Packaging: Transport in sealed, weatherproof bulk bags, containers, or tankers; damage during transit increases dust and spill risk
Separation: Recommended to segregate from oxidizers, acids during shipping; minimize temperature fluctuation in transit where possible to avoid caking at destination
Labelling: Clearly marked product name and hazard warning, especially in ports or customs transfer situations
Worker safety: Remind drivers and loaders to use respiratory protection and avoid inhaling dust; prompt reporting of spillage required during offloading
Classification: Not listed as a hazardous chemical under most international regulations; subject to specific rules for fertilizer use and transport
Reporting requirements: Large-scale spills or runoff into watercourses must be reported to local environmental agencies in many countries
Usage restrictions: Some regions control fertilizer application and storage for environmental protection, requiring special permits or records
Worker safety laws: Governed by national occupational safety agencies; in high-use facilities, inspections may review air quality, personal protective equipment, and handling practices
Labeling: Packaging must show clear, accurate product and safety information in language recognized by destination country
Trade rules: Cross-border transport has varying import/export nitrogen substance regulations, especially in areas with concerns about chemical misuse or agricultural runoff
