Explosives assessment

J.C. Oxley, J.L. Smith, E. Rogers, X. Dong, Gas Production from Thermal Decomposition of Explosives Assessing the Thermal Stabilities of Energetic Materials from Gas Production Data J. Energ. Mat., 18 (2000), 97-121. 

If the DTA or DSC are used as true screening tools in experimental safety testing, which in other words, means that there is not much more information available on the substance to be tested than the explosibility assessment according to the oxygen balance calculation, it may generally be recommended to use stainless-steel sample containers, which can withstand pressure up to 200 bar for the first tests. 

Field, P, Explosability Assessment of Industrial Powders and Dusts, HMSO, London (1983) Dewis, M. and Stranks, j.. Fire Prevention and Regulations Handbook, Royal Society for the Prevention of Accidents, Birmingham (1989)... 

The first major hazard in process plants is fire, which is usually regarded as having a disaster potential lower than both explosion or toxic release. However, fire is still a major hazard and can, under the worst conditions, approach explosion in its disaster potential. It may, for example, give rise to toxic fumes. Let us start by examining the important factors in assessing fire as a hazard. 

B. C. Pol and M. B. Ryan, Database Assessment of Pollution Control in the Military Explosives and Propellant Production Industry final report ORNL-22, Oak Ridge National Lab., Term., Feb. 1986. 

D. Layton and co-workers. Conventional Weapons Demilitarisation, A Health and Environmental Effects Data Base Assessment Explosives and Their Co-Contaminants, UERL-21109, Livermore National Lab., University of California, Livermore, Dec 1987. 

The next part of the procedure involves risk assessment. This includes a deterrnination of the accident probabiUty and the consequence of the accident and is done for each of the scenarios identified in the previous step. The probabiUty is deterrnined using a number of statistical models generally used to represent failures. The consequence is deterrnined using mostiy fundamentally based models, called source models, to describe how material is ejected from process equipment. These source models are coupled with a suitable dispersion model and/or an explosion model to estimate the area affected and predict the damage. The consequence is thus determined. 

Methods for performing hazard analysis and risk assessment include safety review, checkhsts, Dow Fire and Explosion Index, what-if analysis, hazard and operabihty analysis (HAZOP), failure modes and effects analysis (FMEA), fault tree analysis, and event tree analysis. Other methods are also available, but those given are used most often. 

The Effects of Explosions in the Process Industries, Eoss Prevention bulletin 068, Overpressure Working Party, Major Ha2ards Assessment Panel, Institution of Chemical Engineers, Apr., 1986. 

Explosion protection encompasses the measures implemented against explosion hazards in the handhng of combustible substances and the assessment of the effectiveness of protective measures for the avoidance or dependable reduc tion of these hazards. The explosion protection concept is vahd for all mixtures of combustible substances and distinguishes between ... 

Maximum Pressure and Rate of Pressure Rise and KJ These explosibility parameters are used in assessing whether equipment will contain the maximum pressure developed during deflagration, or to design deflagration relief vents and other explosion prevention systems (see NEPA 68 and 69). The test method is given in ASTM E 1226. 

Assessing fire or explosion risks from atmospheres eontaining flammable gas, vapour or dust. Determining oxygen eontent of the working atmosphere. 

HS(Gjl46 Dispensing petrol - assessing and controlling the risk of fire and explosion at sites where petrol is... 

Program created for DOT, EPA, and FEMA to aid emergency preparedness personnel in assessing the sequence and nature of events that may follow an accident. ARCHIE incorporates several estimation methods that may be used to assess the vapor discharge, fire, and explosion impacts associated with episodic discharges of hazardous materials. 

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. 

The investigating team was charged to realisticaHy assess the risk at individual installations before considering interactions that may arise from fires, explosions and the release of airborne toxic substances and other interactions between installations. 

Typical events that are considered are fire, explosion, ship collision, and the failure of pressurized storage vessels for which historical data established the failure frequencies. Assessment of consequences was based partly on conservative treatment of past experience. For example ilic assessment of the number of casualties from the release of a toxic material was based on past histoiy conditioned by knowledge of the toxicology and the prevailing weather conditions. An altemati. e used fault trees to estimate probabilities and identify the consequences. Credit is taken in this process for preventative measures in design, operation, and maintenance procedures. Historical data provide reliability expected from plant components and humans. 

Parallel to the frequency assessment, the consequences of the scenarios were calculated for the effects on the public and plant personnel of chemical release through the rupture disc and fire and explosion. 

Safety air technology, including risk assessment, that minimizes damages and hazards caused by accidents, fire, and explosion... 

In the application of the multienergy concept, a particular vapor cloud explosion hazard is not determined primarily by the fuel-air mixture itself but rather by the environment into which it disperses. The environment constitutes the boundary conditions for the combustion process. If a release of fuel is anticipated somewhere, the explosion hazard assessment can be limited to an investigation of the environment s potential for generating blast. 

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