Hazard analysis assessment practices

Recent regulatory requirements make hazard analysis/assessment part of the PPE selection process. Hazard analysis and assessment procedures shall be used to assess the workplace to determine if hazards are present, or are likely to be present, which may necessitate the use of PPE. As part of this assessment, employees work environment is to be examined for potential hazards, both health and physical, that are likely to present a hazard to any part of their bodies. If it is not possible to eliminate workers exposure or potential exposure to the hazard through the efforts of engineering controls, work practices, and administrative controls, then proper PPE will need to be selected, issued, and worn. The hazard assessment certification form found in Figure 13.3 may be of assistance in conducting a hazard analysis and assessment. 

More in line with the predictive use of hazards analysis, however, is the experimental and theoretical assessment that the viscosity of the liquid significantly affects this mode of initiation. Such information allows redesign of the process to eliminate handling of low viscosity liquid explosives, and quantitative measurement of the sensitivity of the system to mild shocks as a function of viscosity may allow the optimum level to be selected. This is not necessarily a new concept, only quantified in a different manner. Thirty years ago transporters of neat nitroglycerine in the oil fields were paid 25 a day. The stipend for transporting jellied nitroglycerine was seven dollars, a practical comment on the understood difference in hazard. 

The hazard analysis of any industrial process impacts on risk assessment. Risk assessment involves the estimation of the frequency and consequences of a range of hazard scenarios and of individual and societal risk. The risk assessment process is shown in Figure 3.1. The risk criterion used in hazard analysis is the fatal accident rate (FAR). The FAR is defined as the number of fatalities per 108h exposure. The actual FAR in the U.K. was 3.5 in the chemical industry in 1975. No doubt the ideal FAR value should be zero, which is difficult to achieve in practice. 

The basic objective of hazard analysis is to identify and assess potentially hazardous situations, and their possible consequences and associated risk, in order to provide a rational basis for determining where risk reduction measures are needed. Hazard identification always has been an integral part of design and operational practice. However, it is to a large degree still an informal process depending on the experience of those directly involved. 

Safe unit placement enhances the overall safety of a pilot plant. A containment cell or a separate building is not, however, a guarantee of safety. Other measures include Increased process monitoring of safety specific variables, limiting inventories of hazardous feedstocks and products, detailed hazard analysis and risk assessments, and good design practices. One essential element is to ensure that the pilot plant has adequate space to support its operation. This requires a careful evaluation of the required space before the unit is constructed. While a detailed layout and a careful... 

Safety professionals cannot properly give advice on hazards and risks unless the hazards are analyzed and the risks deriving from them are assessed as to their significance. This chapter works through the process of hazard analysis and subsequent risk assessment. It explores hazard analysis and risk assessment methods, discusses the jeopardy in using some published techniques, and concludes with a practical methodology outline. Since there has been a proliferation of risk assessment matrices in recent years, some of them are examined, for their pros and cons. 

Several texts include hazard analysis and risk assessment decision matrices. Every matrix I found has been adopted from those included in what was originally known as Military Standard—System Safety Program Requirements, MlL-STD-882. Its most recent version is now named Standard Practice for System Safety, MIL-STD-882D, 2000. Influence of that standard will be obvious in the remainder of this chapter. 

Professional safety practice requires that hazards be analyzed, that the risks deriving from those hazards be assessed, and that a risk ranking system be utilized. Also, it must be understood that hazard analysis is... 

Having knowledge of hazard analysis and risk assessment methods and the concept of acceptable risk has become a necessity for the professional practice of safety. 

A job hazard analysis is a job design review that is to assess the physical hazards and the task performance hazards, taking into consideration the capabilities and limitations of people, and their possible quirky behavior. For work hazards that are not to be eliminated or controlled through a redesign initiative, obviously, the appropriate administrative practices would be applied. In so doing, the procedures employed should keep the risks of employee injury or illness or environmental damage at an acceptable minimum. 

System safety is hazards-focused, as are all the subsets of the practice of safety, whatever they are called. System safety commences with hazard identification and analysis. Do that poorly, and all that follows is misdirected. Applications of the hazard analysis and risk assessment methods developed in the evolution of system safety have been successful. The generalist in safety practice ought to know more about them. As a minimum, generalist safety practitioners should be knowledgeable about these methods Preliminary Hazard Analysis What-If Analysis and Failure Modes and Effects Analysis. (See Chapter 14, Hazard Analysis and Risk Assessment. )... 

A safety management risk assessment techniqne that is used to define and control the hazards associated with a process, job, or procedure. The Job Safety Analysis ensures that the hazards involved in each step of a task are reduced to as low as reasonably practical (ALARP). The assessment starts with a summary of the entire job process. The job is broken into smaller steps and listed in a tabular form. The hazards for each step are then identified and listed. This is repeated for each step in the process and a method of safe work is identified. It may be also called a Job Hazard Analysis (JHA). See also As Low As Reasonabfy Practical (ALARP). 

This second edition of a Basic Guide to System Safety has been designed to provide the reader with a fundamental understanding of the system safety discipline, the assessment of risk, the hazard analysis process, and some of the common tools and techniques that can be used to determine levels of hazard risk. Numerous examples have been developed throughout the text in an attempt to demonstrate the applicability of system safety engineering and analysis in the practice of the industrial safety and health professional. 

Several methods are available for identifying and assessing hazards (Kletz, 1990). Hazards can be identified through checklists, failure mode effect analysis (FMEA), fault tree analysis, event tree analysis, what-if analysis, and hazard and operability studies (HAZOP). Assessing hazards can be done through hazard analysis (HAZAN), codes of practice, the Dow Explosion Index, and prototype index of inherent safety (PIIS). 

Recent developments take the risk assessment subject to a higher level within the practice of safety. By formalizing the hazard analysis and risk assessment process, a better appreciation of the significance of individual risks is achieved. As risks levels are categorized and prioritized, more intelligent decisions can be made with respect to their elimination or reduction. For the hazard analysis and risk assessment process, it is necessary to arrive at definitions of hazards, hazards analyses, risks, and risk assessments. 

Making a hazard analysis is necessary to and precedes making a risk assessment. William Johnson said this about hazard analysis in MOST Safety Assurance Systems. Hazard analysis is the most important safety process in that, if that fails, all other processes are likely to be ineffective. Johnson s premise is sound Hazard analysis is one of the most significant fundamentals in the practice of safety and will be elaborated on here. 

The original use of the preliminary hazards analysis (PHA) technique was to identify and evaluate hazards in the early stages of the design process. However, in actual practice the technique has attained much broader use. The principles on which preliminary hazards analyses are based are used not only in the initial design process, but also in assessing the risks of existing products or operations. 

A simple, practical and generic hazard analysis and risk assessment process is to be developed that has the potential to be incorporated in all Bll standards. The process must apply to both suppliers and users. 

The job hazard analysis is a very important and effective process to determine hazardous conditions, unsafe practices, and system weaknesses. In this process the supervisor and an employee work together to analyze the specific task. The employee is observed performing the task. Next, they break the task down into steps. At this point, they jointly assess each step to identify any conditions and practices that might cause an injury/illness. Next, they work together on means and methods to eliminate those hazards. They revise procedures to make the task less hazardous. The supervisor, safety director, or safety committee should then take the process to its completion by uncovering the systems weaknesses related to the hazards found during the JHA. 

Where multiple, diverse hazards exist, the practical approach is to treat each hazard independently, with the intent of achieving acceptable risk levels for all. In the noise and toluene example, the hazards are indeed independent. In complex situations, or when competing solutions to complex systems must be evaluated, the assistance of specialists with knowledge of more sophisticated risk assessment methodologies such as Hazard and Operability Analysis (HAZOP) or Fault Tree Analysis (FTA) may be required. However, for most applications, this author does not recommend that diverse risks be summed through what could be a questionable methodology. 

As a practical matter, having knowledge of three risk assessment concepts will be sufficient to address most, but not all, risk situations. They are Preliminary Hazard Analysis and Risk... 

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