Reactive hazards explosive

The information to be compiled about the chemicals, including process intermediates, needs to be comprehensive enough for an accurate assessment of the fire and explosion characteristics, reactivity hazards, the safety and health hazards to workers, and the corrosion and erosion effects on the process equipment and monitoring tools. Current material safety data sheet (MSDS) information can be used to help meet this requirement but must be supplemented with process chemistry information, including runaway reaction and over-pressure hazards, if applicable. 

Reactive hazards, 44, 228 explosive, 235 mixtures, 231, 468 pyrophoric, 17, 214 thermal runaway, 252 unstable, 228 water-sensitive, 228... 

Although I had been aware during most of my career as a preparative chemist of a general lack of information relevant to the reactive hazards associated with the use of chemicals, the realisation that this book needed to be compiled came soon after my reading Chemistry Industry for June 6th, 1964. This issue contained an account of an unexpected laboratory explosion involving chromium trioxide and acetic anhydride, a combination which I knew to be extremely hazardous from close personal experience 16 years previously. 

Where two or more elements or compounds are involved in a reactive hazard, and an intermediate or product of reaction is identifiable as being responsible for the hazard, both reacting substances are normally cross-referred to the identified product. The well-known reaction of ammonia and iodine to give explosive nitrogentriodide-ammonia is an example of this type. The two entries Ammonia Halogens Iodine Ammonia... 

Chemical plants contain a large variety of hazards. First, there are the usual mechanical hazards that cause worker injuries from tripping, falling, or moving equipment. Second, there are chemical hazards. These include fire and explosion hazards, reactivity hazards, and toxic hazards. 

A chemical reactivity hazard, as the term is used in this publication, is a situation with the potential for an uncontrolled chemical reaction that can result directly or indirectly in serious harm to people, property or the environment. The uncontrolled chemical reaction might be accompanied by a temperature increase, pressure increase, gas evolution or other form of energy release. It need not be explosive to result in serious harm. For example, gases evolved from a chemical reaction can be flammable, toxic, corrosive, hot, or can pressurize an enclosure to the point of rupture. 

Damaging fires are uncontrolled chemical reactions, so fire hazards involving ordinary flammable and combustible materials could be included in the above definition of chemical reactivity hazards. However, this publication seeks to supplement basic fire prevention and protection measures by addressing how to successfully manage other chemical reactivity hazards in the work environment. Consequently, the use of the term "chemical reactivity hazards" in this publication will not include explosion, fire and dust explosibility hazards involving the burning of flammable and combustible materials in air. Storage and use of commercial explosives is also outside the scope of this publication. 

During the development of a new facility or process, or when introducing a new process into an existing facility for the first time, an inherent safety review can be conducted to understand the chemical reactivity hazards and explore hazard reduction alternatives. The review need not be limited to chemical reactivity hazards. It can be used to address all other types of process hazards at the same time, including flammability/ combustibility dust or mist explosibility elevated or reduced pressures or temperatures phase differences and health hazards such as toxicity, corrosivity, and asphyxiation. 

Shutting down a process, either for an indefinite period of time or permanently, can introduce chemical reactivity hazard management considerations. For example, one facility wanted to dismantle some equipment for a process for which an ether was a feedstock. A review of facility records did not conclusively reveal whether the equipment had been thoroughly decontaminated after the process was shut down years before. This left open the possibility that the equipment might contain explosive peroxides that could have formed over time by peroxidation of the ether. In another example, an unstable byproduct exploded when piping removed from a process unit was being cut into smaller pieces for disposal. 

When the NFPA diamond is used for container or vessel labeling, and the white (bottom) quadrant contains the W symbol, the material will react violently or explosively with water, and a chemical reactivity hazard obviously exists. However, if the W symbol is not present, the material may still be water reactive, but at a slower rate, since the pur-pose of the NFPA symbol is to alert emergency responders to significant, immediate water reactivity n. hazards. Water reactivity is often very rapid, but can j also be slow. The reaction may generate sufficient gas Twy to rupture a closed container or vessel. The reaction of f an organic material with water may be delayed due to reaction only occurring at the interface. 

If the answer to Question 11 is YES, then you should make use of the information in Chapter 4, because a chemical reactivity hazard is present. The essential practices presented in Chapter 4 should be sufficient to manage this type of chemical reactivity hazard, excluding considerations for commercial explosives, which are also self-reactive materials. 

Uncontrolled reactions have led to serious explosions, fires, and toxic emissions. The impacts may be severe in terms of death and injury to people, damage to physical property, and effects on the environment. In particular, incidents at Napp Technologies in 1995 and Morton International in 1998 raised concerns about reactive hazards to a national level. These and other incidents across the United States2 underscore the need to improve the management of reactive hazards. 

Many materials in common use today have obvious reactivity hazards, for example, explosives, laboratory chemicals, and raw materials to make plastics and other useful products. Yet they are handled safely every day. How Their hazards have been recognized and controlled so that undesirable events (those which can cause loss and harm) do not happen. Your first source of information for controlling hazards should always be your material supplier. 

The data to be listed on the Material Technical Sheet needs to be comprehensive enough for an accurate assessment of the fire and explosion characteristics, reactivity hazards, corrosion or erosion effects, and safety, health, and environmental hazards. 

A reactive hazard exists when changes in chemical structure have the potential to generate heat, energy, and gaseous byproducts beyond that which can be safely absorbed by the immediate surroundings (Bretherick, 1999). If the rate of energy release is rapid enough and not adequately controlled, the consequences may be severe and include fires, explosions, or toxic emissions. 

U.S. Environmental Protection Agency (USEPA), 2000. Case Study Waste Fuel/Oxidizer Reaction Hazards, Prevention of Reactive Chemical Explosions, EPA 550-F00-001, Office of Solid Waste and Emergency Response, April 2000. 

H2 It has a distinctly better thermal conductivity and lower density. Demerits are its reactivity with unsaturated compounds and hazardous explosive nature,... 

Reactivity. A material is considered to be a reactive hazardous waste if it is normally unstable, reacts violently with water, generates toxic gases when exposed to water or corrosive materials, or if it is capable of detonation or explosion when exposed to heat or a flame (40 CFR 261.23). Materials that are defined as forbidden explosives or class A or B explosives by the Department of Transportation are also considered reactive hazardous waste. 

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