Hazard Screening

Use reactor calorimetry testing to determine thermodynamics and kinetics of process. See Appendix 2A (Chemical reactivity hazards screening). 

Such sentinel workflow uses a prediction to select compounds for a more expensive screen that can confirm predicted hazards (liabilities, such as toxicity). It is, provably, the best workflow in contexts where a low prevalence of the hazard is anticipated, and where there is a backstop means further downstream (e.g., preclinical toxicity testing) for detecting hazards before humans are exposed. This workflow then allows the compounds predicted as safe to bypass the expensive hazards screen, without unacceptable risk, and can add significant value in terms of external screening costs or avoiding use of what may be a bottleneck resource. 

A System for Low Cost Thermal Hazards Screening," RADEX-solo, SYSTAG Information Documentation (1990). 

Up to this point, the chemical reactivity hazards of individual substances, either by themselves or in contact with common environmental materials, have been considered. This last question in the chemical reactivity hazards screening will address the potential for an unintended chemical reaction due to incompatible materials contacting each other. Compatibility, in this context, means the ability of materials to exist in contact without specified (usually hazardous) consequences under a defined scenario. A scenario, in this context, is a detailed physical description of the process whereby a potential inadvertent combination of materials may occur (ASTM E 2012-00). 

Hazard Screening Desk Calculation Reaction enthalpy, RXN Need formation energy data or derive it Must know precise stoichiometry Known reactions only, no rate information... 

Banavalik, R., M. Y. Chang, and S. J. M. R. Fitzwater (2002). "Thermal Hazards Screening Study of the Reactions Between Hydrogen Cyanide and Sulfuric Acid and Investigations of Their Chemistry." Ind. Eng. Chem. Res. 41, 145-52. 

The company has a well-equipped laboratory for thermal hazards screening and sophisticated reaction calorimetry. 

The control of chemical hazards at SNL is documented in the Primary Hazard Screen and Hazard Analysis process for every project or facility. Work-specific technical work documents provide more detailed chemical hazard controls. Hazard control is based on the hierarchy of controls engineering controls first, administrative controls next, and personal protective controls last. ES H subject matter experts provide input on appropriate controls to chemical users and their management. 

Manila, M., and Kivi, P. (1989), Job Load and Hazard Analysis A Method for Hazard Screening and Evduation, in Recent Developments in Job Analysis Proceedings of the International Symposium on Job Analysis, K. Landau and W. Rohmert, Eds. (University of Hohenheim, March 14-15), Taylor Francis, New York, pp. 179-186. 

The order in which hazards analyses are carried out is usually determined by a preliminary consequence ranking i.e., those processes which have the potential for creating the most serious consequences are analyzed first. This can be done through the use of a Major Hazards Screening. In practice, the order in which hazards analyses are carried out is also affected by logistical issues such as the availability of up-to-date P IDs or of key personnel to serve as hazards analysis team members. 

During Phase I, the project team will conduct high-level hazards analyses, probably using some form of Major Hazards Screening. The team will be looking for killer problems that are so serious that the project will have to be canceled. The analysis will not consider details on design or the occupational safety and human factors issues discussed in the previous chapters. 

The hazard and accident analysis associated with normal operations is briefly discussed. For illustration, simple examples associated with the U.S. ceramic process will be used. The hazard analysis can be divided into four parts Hazard Identification, Accident Event Characterization, Hazard Controls, and Hazard Screening. 

The hazard analysis may identify many potential accident events. Some may be minor and some significant. For those minor accidents, one can stop here and no further analysis is required. If the hazard analysis indicates that the risk of an accident event is significant, then a detailed quantitative accident analysis will be performed for that accident. The hazard screening allows the major effort of safety analysis to be concentrated on those accidents that are significant. 

Primary Hazard Screening documentation for HCF isotope processing of Sandia Nationai Laboratories Integrated Safety Management System (SNL7A00124-001) ... 

Phase one provides estimates of the consequences based on predetermined data consisting initially of a Primary Hazard Screening submitted by the facility manager. The hazard assessment developed from this becomes the basis for emergency planning. 

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