Dangerous When Wet

Class 4.3 materials are dangerous when wet. The DOT definition is a material that, by contact with water, is liable to become flammable or to give off flammable or toxic gas at a rate greater than 1 liter per kilogram of the material per hour. Examples of water-reactive materials include zinc powder, trichlorosilane, sodium phosphide. 

Rail tank car of air-reactive phosphorus shipped under water. 

Calcium carbide, CaCj, is a binary salt. It is a grayish-black, hard solid that reacts with water to produce acetylene gas, a solid corrosive that is calcium hydroxide, and release heat. Acetylene gas is manufactured by reacting calcium carbide with water. Because acetylene is so unstable, it is not shipped in bulk quantities. 

Closed containers of water-reactive phosphorus pentasultide, which produces toxic hydrogen-sulfide gas upon contact with water. 

The white space at the bottom of the diamond has a W with a slash through it, indicating water reactivity. The primary nse is in the mannfacture of siloxanes, which are straight-chained compounds similar to paraffin hydrocarbons. 

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Dangerous When Wet Shipping Class 4.3 (lATA) Forbidden Passenger Cargo 15-kg Maximum Air Freight Corrosive SoUd Shipping Class 8 (lATA)... 

Calcium carbide is classed as a ha2ardous chemical under Department of Transportation regulations. Domestic shipments are mainly in steel tote bins varying in capacity from 2.5—4.5 t. A small amount continues to be shipped in industrial wide mouth steel dmms of 270 kg capacity. Containers must be marked "Flammable soHd, dangerous when wet" and have the United Nations designation UN 1402. 

Flammable solids Spontaneously combustible materials and Materials that are dangerous when wet... 

Poison A gas explosives-A/B, organic peroxide, flammable solid, materials dangerous when wet, chlorine, flourine, anhydrous ammonia, radioactive materials, NFPA 3 4 for any categories including SF>ecial hazards. PCB s fire, DOT inhalation hazzird, EPA extremely hazardous substances, and cryogenics. 

Substances that are water-reactive will nearly always be identified as such on their MSDSs or ICSCs. They may be identified as DOT/UN Hazard Class 4.3 materials for shipping purposes and labeled as dangerous when wet. However, some water-reactive materials are classified otherwise. Acetic anhydride is designated Class 8 it may also be identified as a combustible liquid. 

Is any substance identified as water reactive YES Sodium hydrosulfite is water reactive uncoated aluminum powder is DOT/UN Hazard Class 4.3, Dangerous When Wet... 

Class 4 Flammable Solid Spontaneously combustible material and Dangerous when wet material... 

Hazard Class 4 - Division 4.3. Dangerous when Wet Materials ... 

DOT CLASSIFICATION 9 Label CLASS 9 (NA 9260) DOT Class 4.1 Label Flammable SoUd (UN 1309) DOT Class 4.3 Label Dangerous When Wet (UN 1396) SAFETY PROFILE Although aluminum is not generally regarded as an industrial poison, inhalation of finely divided powder has been reported to cause pulmonary fibrosis. It is a reactive metal and the... 

ACGIH TLV TWA 2 mg(Al)/m3 DOT CLASSIFICATION 4.3 Label Dangerous When Wet SAFETY PROFILE Hydrides of some metals (such as ASH3) are extremely toxic. Dangerous fire hazard. An unstable material which is spontaneously flammable in air or O2. Evolves explosive H2 upon contact with moisture. Severe explosion hazard by chemical reacdon wherein H2 gas is produced, also in contact with methyl ethers contaminated by CO2. Mixtures with tetrazole derivadves are explosive. Reacts with oxidizing materials. On contact with acid or acid fumes, it can emit toxic fumes. See also HYDRIDES and ALUMINUM COMPOUNDS. 

ACGIH TLV TWA 2 mg(Al)/m3 DOT CLASSIFICATION 4.3 Label Dangerous When Wet, Poison SAFETY PROFILE A poison. Dangerous fire hazard. Evolves spontaneously flammable PH3 in contact with water. See also PHOSPHIDES, PHOSPHINE,... 

DOT CLASSIFICATION 4.3 Label Dangerous When Wet, Corrosive, Flammable Liquid... 

DOT CLASSIFICATION 4.3 Label Dangerous When Wet SAFETY PROFILE Reaction on contact with moisture forms explosive acetylene gas. Flammable on contact with moisture, acid or acid fumes evolves heat or flammable vapors. Moderate explosion hazard. Incandescent reaction with CI2 (245°C), Br2 (350°C), I2 (305°C), HCl gas + heat, PbF2, Mg + heat. Incompatible with Se, (KOH + CI2), AgN03, Na202, SnCb, S, water. Mixtures with iron(III) chloride, iron(III) oxide, tin(II) chloride are easily ignited and burn fiercely. Vigorous reaction with methanol after an induction period. 

DOT CLASSIFICATION 4.3 Label Dangerous When Wet SAFETY PROFILE Poison by ingestion, inhalation, skin contact, intravenous, and intraperitoneal routes. Moderately toxic to humans by ingestion. Questionable carcinogen with experimental tumorigenic data. Mutation data reported. The fatal dose, by ingestion, is probably around 20 to 30 g for an adult. It does not have a cyanide effect. Calcium cyanamide is not believed to have a cumulative action. Flammable. Reaction with water forms the explosive acetylene gas. When heated to decomposition it emits toxic fumes of NOx and CN". See also CALCIUM COMPOUNDS, AMIDES, and CYANIDE. 

DOT CLASSIFICATION 4.3 Label Danger When Wet, Corrosive, Flammable Liquid SAFETY PROFILE Poison by ingestion and inhalation. A severe irritant to skin, eyes, and mucous membranes. Corrosive. Dangerous fire hazard if exposed to heat, open flames, or powerful oxidizers. Will react with water or steam to produce heat and toxic and corrosive fumes. To fight fire, use foam, dry chemical, mist, spray. When heated to decomposition it emits toxic fumes of CL and phosgene. See also CHLOROSILANES. 

DOT CLASSIFICATION 4.3 Label Dangerous When Wet SAFETY PROFILE Moderate inhalation hazard. Low skin toxicity. Reaction with moisture releases hydrogen and acetylene gases, which then ignite impurities in the alloy may liberate such poisonous and reactive gases as phosphine and arsine. Dty mixtures with sodium hydroxide react incandescently when water is added. Reaction with acid, acid fumes, or oxidizing materials can emit toxic fumes. Reaction... 

Dangerous When Wet SAFETY PROFILE See LITHIUM COMPOUNDS for a discussion of the toxicity of the lithium ion. See SODIUM for a discussion of the toxicity of metallic Uthium. 

DOT CLASSIFICATION 4.3 Label Dangerous When Wet (UN 2950) DOT Class 4.1 Label Flammable Solid (UN 1869) DOT Class 4.3 Label Danger When Wet, Spontaneously Combustible SAFETY PROFILE Inhalation of dust and fumes can cause metal fume fever. The powdered metal ignites readily on the skin causing burns. Particles embedded in the skin can produce gaseous blebs that heal slowly. 

DOT CLASSIFICATION 4.3 Label Dangerous When Wet, Flammable Liquid SAFETY PROFILE May ignite spontaneously in air. A very dangerous fire hazard when exposed to heat or flame can react vigorously with oxidizing materials. When heated to decomposition it emits acrid smoke and irritating fumes. See also ETHERS, MAGNESIUM COMPOUNDS, and BROMIDES. 

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