Hazard analysis safety performance measurements

A Safety Case is a narrative that literally makes the case that an adequate level of safety has been reached for an installation. It requires looking at all potential hazards which could lead to a loss of the installation, a loss of life, or a major pollution event. A risk analysis is performed on each hazard evaluating the probability of the event occurring and describing the magnitude of the consequences. A discussion is then given of the measure undertaken to lower the probability of occurrence or to mitigate the consequences and a case is made that the risk for the installation meets the ALARP safety criteria. 

The assumption of independence between hazards and safety instrumented function failures seems very realistic. (NOTE If control functions and safety functions are performed by the same equipment, the assumption may not be valid Detailed analysis must be done to insure safety in such situations, and it is best to avoid such designs completely.) When hazards and equipment are independent, it is realized that a hazard may come at any time. Therefore, international standards have specified that PFDavg is an appropriate metric for measuring the effectiveness of a safety instrumented function. 

Section 3.8.2 System/Cost Effectiveness Analyses. Describes the implementation of system and cost effectiveness analyses to support the development of fife cycle balanced products and processes and to support risk management. Describes the MOEs, how they interrelate, and criteria for the selection of measures of performance (MOPs) to support the evolving definition and verification of the system. Includes description of the overall approach for system/cost-effectiveness analysis as well as manufacturing analysis verification analysis distribution analysis operational analysis hiunan engineering, manpower, personnel, and training analysis usability analysis supportability analysis safety, health hazards, and environmental analysis and life cycle cost analysis. Describes how analytical results will be integrated. 

Emerging concepts of system analysis, accident causation, human factors, error reduction, and measurement of safety performance strongly suggest the practicality of developing a higher order of control over hazards (than currently exists). 

Examples of leading indicators include measures of the quality of an audit program, including schedule adherence, the number of repeat injuries, and analysis of process hazard reviews. As with trailing indicators, there must be some type of cause and effect relationship established between leading indicators and safety performance. 

A job safety assessment or analysis should be performed at the start of any task or operation. The designated competent or authorized person should evaluate the task or operation to identify potential hazards and determine the necessary controls. This assessment should focus on actual worksite conditions or procedures that differ from or were not anticipated in the related project or phase hazard analysis. In addition, the authorized person should ensure that each employee involved in the task or operation is aware of the hazards related to the task or operation and of the measures or procedures that workers and visitors must use to protect themselves. Note The job safety assessment is not intended to be a formal, documented analysis, but instead is more of a quick check of actual site conditions and a review of planned procedures and precautions. A more detailed explanation of job safety analysis is provided in Chapter 12. 

The key to system safety is the management of hazards. To effectively manage hazards, one must understand hazard theory and the identification of hazards. Hazard analysis provides the basic foundation for system safety. It is performed to identify hazards, their effects and causal factors. It is further used to determine system risk, the significance of hazards and to establish design measures that will eliminate or mitigate the identified hazards. 

After the necessary controls have been implemented, it s important to periodically review yom job hazard analysis to ensure that it remains current and continues to help reduce workplace accidents and injuries. Even if the job has not changed, it is possible that dming the review process you will identify hazards that were not identified in the initial analysis. It is particularly important to review your job hazard analysis if an illness or injury occirrs on a specific job. Based on the circumstances, you may determine that you need to change the job procedure to prevent similar incidents in the futru e. If an employee s failure to follow proper job procedures results in a near miss, discuss the situation with all employees who perform the job and remind them of proper procedures. Any time you revise a job hazard analysis, it is important to train all employees affected by the changes in the new job methods, procedures, or protective measures adopted. Remember, a JHA is one component of the larger commitment of a safety and health management system. 

All recruitment and selection activities should begin with a job analysis. Job analysis allows the task requirements of a job to be precisely determined. Furthermore, job analysis allows the safety risks associated with a job to be determined, and also the identification of the knowledge, skills, and abilities required to work, both safely, and at a satisfactory performance level. It is well established that the occupation or job a person is performing substantially influences accident vulnerability (Ford and Wiggins 2012). In other words, it is vital for safety, for the specific hazards and risks associated with a job to be identified, and conducting a job analysis is an approach which can be used to collect this information. Without the essential information which job analysis provides, it is impossible to provide job applicants with a realistic safety preview for the job (see Chap. 3, Sect. 3.7.2.1), and difiicult to know what competencies a new employee needs to bring to the job, and therefore what should be measured in a selection program. 

This paper presents a new approach based on a combination of traditional predictive modelling and event/fault tree analysis techniques, which allows representing at the same time evolution of hazards and normal and abnormal (i.e. failures) performance of safety measures, e.g. variations of process parameters, analysis and inspections, through the food chain for a better estimation of the real impact of such deviations/failures on consumer health. 

Performing JSAs is a complex process. To better understand the importance of this analysis tool, figure 9-7 shows a completed JSA for hydraulic line replacement. Please note accident categories described in the potential hazards section. These potential hazards will aid in determining what safety measures and personal protective equipment are necessary for a given job. 

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