Chemical Hazard Analysis

Federal Emergency Management Agency (FEMA), U. S. Department of Transportation (DOT), and U. S. Environmental Protection Agency (EPA) (ca. 1989). Handbook of Chemical Hazard Analysis Procedures. Washington, D. C. FEMA Publications Office. 

Emergency Management Agency, Handbook of Chemical Hazard Analysis Procedures, p. 6-7, 1989). It is likely that the absorption process functions in proportion to the square root of the duration of exposure (Perry, Chemical Engineers Handbook, 4th ed., p. 14-13 and Figs. 14-7, 14-9, and 14-21, 1963). 

Not every reaction should be subjected to full chemical hazard analysis, as some reactions, e.g., the hydrolysis of an ester in water, will have little... 

What are the qualifications of personnel performing chemical hazard analysis Are "hands-on" employees involved in all chemical hazard analyses conducted by SMEs Do environment, safety and health (ES H) professionals conduct walk-downs of feciUties in which chemicals are to be used... 

Joint documents (EPA, Federal Emergency Management Agency, and DOT), Technical Guidance for Hazards Analysis, Emergency Planning for Extremely Hazardous Substances, and Handbook of Chemical Hazard Analysis Procedures. 

Chemical Hazard Analysis (CHA)— A CHA is derived from HAZOP methodologies and can be considered a precursor to a PHA. It is applicable to analyzing petrochemical or chemical processing hazards. The same seven basic HAZOP guidewords are used no, more, less, part of, reverse, as well as, and other. While CHA assumes the proposed chemical reaction is basically safe when conducted as specified (should... 

CHAZOP a Computer Hazard and Operability study. A structured qualitative study of control and safety systems to access and minimize the effect of failures of its subsystems impacting the plant or affecting the ability of an operator to take corrective action Chemical Hazard Analysis (CHA) a formal process for identifying and quantifying reactive chemical hazards... 

The purpose of hazard analysis and risk assessment ia the chemical process industry is to (/) characterize the hazards associated with a chemical facihty (2) determine how these hazards can result in an accident, and (J) determine the risk, ie, the probabiUty and the consequence of these hazards. The complete procedure is shown in Figure 1 (see also Industrial hygiene Plant safety). 

For chemical faciUties in the United States, hazard analysis is not an option if inventories of hazardous chemicals are maintained in amounts greater than the threshold quantities specified by the Occupational Safety and Health Administration (OSHA) regulation 1910.119. Many faciUties are finding that hazard analysis has many benefits. The process or procedure often works better, the quaUty of the product is improved, the process experiences less down time, and the employees feel more comfortable in the work environment after a hazard analysis has been completed. 

An important part of hazard analysis and risk assessment is the identification of the scenario, or design basis by which hazards result in accidents. Hazards are constandy present in any chemical faciUty. It is the scenario, or sequence of initiating and propagating events, which makes the hazard result in an accident. Many accidents have been the result of an improper identification of the scenario. 

Conduct Hazard Analysis and Risk Assessment. Ahazardis any biological, chemical, or physical property that may cause an unacceptable consumer health risk. AH of the potential hazards in the food chain are analyzed, from growing and harvesting or slaughtering to manufacturing, distribution, retailing, and consumption of the product. 

Stanley M. Englund/ M S / Ch E / Fellow American Institute of Chemical Engineers Process Consultant, The Dow Chemical Company (retired). (Section Editor, Section 16 Introduction Hazard Analysis Storage and Handling of Hazardous Materials Reactive Chemicals Combustion and Flammability Hazards Hazards of Vacuum Hazards oflnei t Gases)... 

Process Hazard Analysis (PHA) (Dowell, 1994, pp. 30-34.) The OSHA rule for Process Safety Management (PSM) of Highly Toxic Hazardous Chemicals, 29 CFR 1910.119, part (e), reqmres an initial PHA and an update every five years for processes that handle listed chemicals or contain over 10,000 lb (4356 kg) of flammable material. The PHA must be done by a team, must include employees such as operators and mechanics, and must have at least one person skilled in the methodology employed. Suggested methodologies from Process Safety Management are listed in Table 26-1. 

Chemical Exposure Index (CEI) Chemical Exposure Index, 1994). The CEI provides a method of rating the relative potential of acute health hazard to people from possible chemical release incidents. It may be used for conducting the initial process hazard analysis and it establishes the degree of mrther analysis needed. The CEI also may be used as part of the site review process. 

Two standard estimation methods for heat of reaction and CART are Chetah 7.2 and NASA CET 89. Chetah Version 7.2 is a computer program capable of predicting both thermochemical properties and certain reactive chemical hazards of pure chemicals, mixtures or reactions. Available from ASTM, Chetah 7.2 uses Benson s method of group additivity to estimate ideal gas heat of formation and heat of decomposition. NASA CET 89 is a computer program that calculates the adiabatic decomposition temperature (maximum attainable temperature in a chemical system) and the equilibrium decomposition products formed at that temperature. It is capable of calculating CART values for any combination of materials, including reactants, products, solvents, etc. Melhem and Shanley (1997) describe the use of CART values in thermal hazard analysis. 

Cronin, J. E. A Strategy for Thermal Hazards Analysis in Batch Chemical Manufacture, Thesis, Department of Chemical Engineering, South Bank Polytechnic, 1987. 

In order to understand the chemical and process hazards, a Process Hazard Analysis (PHA) should be conducted. For tolls involving... 

Process Hazard Analysis (PHA) An organized effort to identify and evaluate hazards associated with chemical processes and operations to enable their control. This review normally involves the use of qualitative techniques to identify and assess the significance of hazards. Conclusions and appropriate rec-... 

The handbook additionally provides an extensive overview and comparison of commercially available computer systems and software for chemical emergency planning. This section provides technical guidance for hazard analysis and identification implementing regulatory requirements and descriptions of computer applications and systems applicable under SARA Title III. 

This valuable reference volume conveys a basic understanding of chemical reactor design methodologies that incorporate both scale-up and hazard analysis. It shows readers how to select the best reactor for any particular chemical reaction, how to estimate its size, and how to obtain the best operating conditions. 

PSM was created to help the management of hazards associated with processes using highly hazardous chemicals. In an appendix to the rule, OSHA discussed several methods of process hazard analysis. That... 

Complete and accurate written documentation of chemicals properties, process teclinology, and process equipment is essential to the PSM program and to a process hazards analysis (PrHA). This information serves many users including the PrHA team. The needed chemical information includes fire and explosion characteristics, reactivity hazards, safety and health hazards and the corrosion and erosion effects. Current material safety data sheet (MSDS ) information helps meet this requirement, but must be supplemented with process chemistry information regarding runaway reactions, and over-pressure hazards. 

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