Explosion potentials, definition

Accidental explosions arc potentially the most dmigcrous Uiey arc a major concern for any industrial plant that deals with either pressurized or flammttble gases. An accidental explosion occurs not by design and tliercforc is not similar to an intentional e.xplosion, where the conditions are planned and can be controlled. Accidental e.xplosions usuttlly arc the result of equipment failure or operator error. Although accidental explosions are by definition unforeseen events, tlie procedures discussed in the ne.xt chapter may be implemented either to minimize tlieir effects or to prevent tlicm entirely. 

The potential of ultrahigh-resolution mass spectrometry for the analysis of complex chemical mixtures is particularly illustrated by FT-ICR-MS which definitely sets a new standard. For example, ultrahigh-resolution was applied to separate several thousand components in crude oil, [85,86] fuels, [87,88] or explosion residues. [89]... 

Greenet (Ref 1, p 565) defined it as "a thermodynamic machine by which the potential energy of the explosive is converted into the kinetic energy of the projectile . Although he does not describe in his book any artillery pieces, the meaning of his definition is that... 

Potential (Potential or Effet utile, in Ft). According to definition given in Refs 1 2 it is equal to QX425 kg-m/kg, where Q is heat of ezpln in Kcal/kg and 425 is mechanical equivalent of heat. This unit is identical with W which is the maximum quantity of work that can possihly be done by a unit weight of the explosive A slightly different definition is given by Muraour(Ref 3) the potential de V exp Iosif is equal to QX428, where Q is the heat evolved on decomposition of 1 kg of explosive and 428 is the mech equlv of heat. 

The Institution also developed definitions for a chemical hazard and a major hazard. It called a chemical hazard a hazard involving chemicals or processes which may realize its potential through fire, explosion, toxic or corrosive effects and, a major hazard as an imprecise term for a larger scale chemical hazard, especially one which may be realized through an acute event . 

The word toxic is considered as synonymous with harmful and poisonous , with regard to the effects of these chemicals [6]. However, although toxicity , simply, is the ability of a substance to cause injury to biological tissue , the hazard (or risk) posed by a substance is the probability that this substance can cause injury in a given environment , which is broader in definition. The hazard posed by any substance is characterised by factors such as its toxicity, the details of its absorption and metabolisation as well as excretion, its speed of action, perceptible signs of its possible hazard(s), and its potential (if there is any) for fire or explosion. 

These regulations illustrate a trend that is occurring in safety legislation, which is now starting to move from a prescriptive approach with definitions of what has to be done in specific situations to a more risk-based approach where the precautions and actions taken are left to the individual user provided they meet certain risk-based criteria. A proposed European Directive concerning minimum requirements for improving the safety and health of workers potentially at risk from explosive atmospheres extends this concept to all work places where flammable atmospheres may be formed. When adopted, this will require all employers to carry out a hazard assessment to identify whether a flammable atmosphere is likely to exist and, where so, to demonstrate that appropriate technical, organisational and other measures appropriate to the nature of the operation have been taken to minimise the risk. 

Unlike many products that burn or explode when exposed to heat or pressure, explosives are examples of the static potential of chemical energy in that they release their energy only when determined by the user. Instead of uncontrollable reactions, explosives can be manufactured, stored, and used when needed, a safe and predictable application for a potentially dangerous product. Because of their potential to convert mass into heat and energy, explosives are by definition a very hazardous product. The usefulness of their properties, however, means that explosives are constantly needed— and improved. Consequently, more powerful explosives constantly appear, and the methods for using them safely also keep pace. 

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