A violent, explosive decomposition reaction can occur. Acetylene is a colorless, combustible gas with a distinctive odor. Hazards of Acetylene Gas. Therefore, acetylene stored with acetone solution under 10 atm pressure, acetone absorbed some porous materials for settings safety of the cylinder or suppliers tank. Since the 1950s, acetylene has mainly been manufactured by the partial combustion of methane. For a long time, it was assumed to have the unusual property that on ignition it does not evolve any gas, only decomposing through the reaction: Ag 2 C 2 (s) → 2 Ag (s) + 2 C (s) per square inch. This post specifically concentrates on hazards as well as safe storage of compressed acetylene gas cylinders along with some additional information. 5.2. As the gas is highly combustible when comes in contact with the oxygen, it is recommended to ensure safety measures to avoid accidents. It forms explosive mixture with the air. This gas has the widest explosive range of any commonly used gas. See CGA Pamphlet SB-4, Handling Acetylene Cylinders in Fire Situations, for further information. Thus, their careful handling and storage is very important. Flammable vapors may spread from leak, creating an explosive reignition hazard. (8) is 600 Pa s, which is much less than the right side. Acetylene leaks, no matter how small, can have serious consequences. Care must be taken to ensure that extinguishing the fire will not increase the hazard of explosion or lack of oxygen by allowing acetylene to accumulate in an unventilated area. Flammable Gas Incompatibilities & Reactivities Zinc; oxygen & other oxidizing agents such as halogens [Note: Forms explosive acetylide compounds with copper, mercury, silver & brasses (containing more than 66% copper).] Acetylene reacts with active metals (e.g., copper, silver, and mercury) to form explosive acetylide compounds. Pure acetylene is a colourless gas with a pleasant odour; as prepared from calcium carbide it usually contains traces of phosphine that cause an unpleasant garliclike odour. Some tips for safely using and storing acetylene: Always use acetylene in a well vented area, and never in a confined space. Stating that an acetylene cylinder is equivalent to x kg of TNT is little different to saying the same about a car’s petrol tank, a camping gas or propane cylinder, or even your kitchen’s gas hob being equivalent to a certain amount of high explosive. It is very flammable and can bring disastrous accidents if not handled with precautions. Acetylene gas leaking from a supply tube was ignited by the source flame and a minor explosion occurred, and appears to have damaged both gas supply lines, which led to a second major explosion and fire. The other property of acetylene which you must remember is this: that the flammability range of mixtures of air and acetylene is broader than that of any other fuel gas/air mixture. If venting or leaking gas catches fire, do not extinguish flames. Acetylene is highly shock sensitive and is a flammable gas that is unstable in certain conditions, which may decompose explosively. Explosive character. • Acetylene regulators clearly indicate pressure at or above 15 psig with red marking on the gauge. acetylene gas is not explosive. Handling Acetylene Cylinders in Fire Situations, for further information. 4.0% vol. Pure silver acetylide is a heat- and shock-sensitive high explosive. Acetone . Acetylene is a reactive material that poses a fire and explosion hazard. I did it outside and the wind blew out my burning splint. 2.5% vol : Hydrogen . It is a recovered side product in production of ethylene by cracking of hydrocarbons.Approximately 400,000 tonnes were produced by this method in 1983. per square inch. According to legislation, this gas should not be compressed freely to more than 20-22 lbs. Acetylene . 1.1% vol. No water or water-based foams shall be used in such situations. This gives the liquid acetone time to return to its correct place in the porous mass. Our member concluded: Flashbacks are commonly caused by a reverse flow of oxygen into the fuel gas hose (or fuel into the oxygen hose), producing an explosive mixture within the hose. It may react explosively even in the absence of air at elevated pressure and/or temperature. Even a small cylinder of the substance can cause a great deal of damage and injury to people and pets. Acetylene can be decomposed to its elements with the liberation of heat. Precautionary Statements: Read label before use. This involved some 6 cu m of acetylene and 18 cu m of nitrous oxide, and caused severe structural damage. 2.5% vol : Hexane . Compressed Acetylene Gas (215) 898-4453 Office of Environmental Health and Radiation Safety (EHRS) www.ehrs.upenn.edu Rev. Flammable vapors may spread from leak, creating an explosive reignition hazard. Special hazards arising from the substance or mixture Fire hazard : EXTREMELY FLAMMABLE GAS. Pure acetylene is a unique gas with hazards that arise from its high energy bonds and flammability. Storing a flammable gas needs more precautions than regular gas types. Carleton University, Ottawa, Canada. Bulk gas storage has a minimum separation of 3 meters. THE EXPLOSIVE DECOMPOSITION OF ACETYLENE IN PIPELINES By F. W. S. CARVER,† C. M. SMITH, † and G. A. WEBSTER† SYNOPSIS Studhies of the self-decomposition characteristics of acetylene in pipelines have been made as a function of tube diameter, initial pressure, energy of initiation and diluent concentration. For an acetylene gas detonation, the pressure can suddenly increase by a factor of up to 40 (Miller, 1965). As a result special precautions are required during its production and handling. When mixed with air, the explosive range is from 2.5% to 82%. Its presence in ethylene is usually undesirable because of its explosive character and its ability to poison … Read Safety Data Sheet before use. Its lower and upper explosive limits in air are 2.5% and 93%, respectively. (In the latter case an effectively unlimited quantity of high explosive.) Failure to do so can cause quality problems with acetone liquid getting into the gas. If venting or leaking gas catches fire, do not extinguish flames. When mixed with pure oxygen in a cutting torch assembly, an acetylene flame can theoretically reach over 5700°F. Acetylene is the most common gas used for fueling cutting torches in both general industry and the mining industry. However, free acetylene can undergo explosive decomposition when compressed or overheated. For the exact product composition, please refer to Air Products technical specifications. They are often explosive, combustible, poisonous, corrosive, or may offer a combination of all these hazards. Asutent crosses to the areeding pes plans, one with green pots and fie atter with yellow patis. It helps to burn the object at an increased rate. Acetylene gas explosion: ‘Hundreds could have died’ DEVASTATION: Above, some of the damage in Wolsingham in the immediate aftermath of the explosion that killed Andy Herd 0 comment Order 1947 made under the Explosives Act 1875) defines acetylene gas at pressures of more than 9psi (0.621 BAR) above that of the atmosphere as being an 'explosive' and requires that it may not be held: (a) at pressures in excess of 9psi (0.621 BAR) above that of the atmosphere, except as approved by the Secretary of State, nor Acetylene is commonly used for fueling cutting torches in both general industry and the mining industry. Acetylene is commonly used in gas cutting. Unlike oxygen, acetylene cannot be compressed freely with safety to a pressure greater than 30-40 lbs. These same prop-erties give acetylene its value as a high temperature cutting and welding gas with a very wide range of applications. The decomposition may or may not give rise to explosion, depending on conditions. For safety reasons, the acetylene is dissolved in acetone or dimethylformamide in the gas receptacle. Because of the fact that propane, hydrogen, butane, methane, ethylene, acetylene, ammonia, ethane and silane gas are all flammable, and therefore dangerous gas, it is essential to store these gas safely and correctly. Acetylene gas forms a explosive mixture in contact with air. Let’s explain that more fully: Acetylene/air mixtures can be ignited when they contain anywhere from 2.5 percent acetylene to 80 percent acetylene. When acetylene is liquefied, compressed, heated, or mixed with air, it becomes highly explosive. This paper considers the explosion of an acetylene gas cylinder, which occurred in 1993 in Sydney. Explosive, fire, blast or projectile hazard. Acetylene 74-86-2 100 % Concentration is nominal. Preparation. Fire hazard : EXTREMELY FLAMMABLE GAS. Acetylene for instance, the gas used in an acetylene torch used to cut metal will combust or explode anywhere from 2.5% concentration all the way up to 100%. A value for t{ is given in Lees (1996) as 10" 5 s. Thus, for a gas explosion, the left-hand side of Eq. Acetylene cylinders are to be used and stored only outdoors or in a well ventilated place. Acetylene gas is considered to be a hazardous gas. The following are the lower explosive limits (LEL) of selected gases. A back flow preventive device is used in case of piping the gas. At 40 times original pressure, Pex is 60 MPa. Dangerous stuff. In addition to the acetylene, oxygen is widely used too for gas cutting. Every gas has a range in which it can combust or burn. 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