Risk assessment hierarchy

Several authors have provided comparative summaries of hazard and risk ranking tools. One publication organized examples of related hazard ranking tools according to a hierarchy based on the complexity of hazard and risk assessment decisions being supported. This relationship is shown in Figure 1. 

In the opening chapter of this book, reference is made to the hierarchy of some of the relevant international and European legislation and its influence on the development of risk-based approaches to help manage and control hazardous substances. Reference is made also to the central role of ecotoxicity testing in risk assessment. 

Compliance with the Carcinogens Directive requires the employer to assess the risk of exposure, and the nature and degree of that risk. The hierarchy of control mechanisms, in descending order of preference, is ... 

However, this has led to a substitution of PPE for safety itself, a consequence at direct odds with accepted risk assessment philosophy. Whichever hierarchy of risk reduction is utilised, PPE is always near the bottom in terms of a risk reduction strategy, if not actually in last place. The Health and Safety Executive (2003) states that PPE should be the last resort in health and safety management, yet its visibility and prominence within the construction site environment has led to a social construction of safety so tightly interwoven with PPE that the two are rarely separated. Although PPE is certainly an artefact of safety, it is not safety itself, and it is important that this distinction should be explored to ensure it is better understood. 

In this paper, the AHP analytic hierarchy process method [7] is used to determine the weighting of risk assessment index. Due to the limited paper length, the calculation method for AHP weighing is omitted. Here, it is assumed that the AHP weighing is... 

When required by the results of the risk assessment, alternate proposals for the design and operational changes necessary to achieve an acceptable risk level would be recommended. In their order of effectiveness, the action listing shown in The Safety Decision Hierarchy mentioned in Chapter 15, Acceptable Risk, would be the base upon which remedial proposals are made. For each proposal, remediation cost would be determined and an estimate of its effectiveness in achieving risk reduction would be given. 

Although a hazard analysis and a risk assessment would result from applying the preceding outline, good management requires that the remaining steps in The Safety Decision Hierarchy be taken, which are—decide and take action, and measure for effectiveness. 

For risk assessment, a DSS (Lopes et al, 2009) is used that incorporates a decision model proposed by Brito Almeida (2009). This DSS is a system designed to assess risk levels of each pipeline section with its characteristics, ranking all sections in a multidimensional hierarchy of risk, based on Multi Attribute Utility Theory (MAUT). 

Risk assessment represents a careful analysis of the premises, processes and work activities to identify what could cause harm to people to enable decisions to be made as to whether sufficient precautions have aheady been taken or whether further controls are needed. The aim of Risk Assessment it to individualize a risk priority that allows to define a hierarchy of intervention activities (design review, procedures, formation and information) needed to eliminate or reduce the risk. There are many methods for Risk Assessment (FMEA, FTA, HAZOP, What-if, MOZAR, etc.) (Hiromitsu 1996) that are all usable. 

Manuele, Fred A. Risk Assessment and Hierarchies of Control. Professional Safety, May 2005. 

In that text, the discussion of each step is extensive. Comments will be made here on the first two only. The remaining steps are addressed in Chapter 12, Hierarchy of Controls The Safety Decision Hierarchy. For Step 1,—Identify the hazards—the hazard analysis and risk assessment methodologies are as shown in Table 2. 

The Department of Defense s Standard Practice for System Safety, MIL-STD-882, was originally issued in 1969. It was a seminal document at that time, and three revisions of it have been issued over the span of 31 years. This standard has had considerable influence on the development of risk assessment, risk elimination, and risk control concepts and methods. Much of the wording on risk assessments and hierarchies of control in safety standards and guidelines issued throughout the world is comparable to that in the various versions of MIL-STD-882. 

In Innovations in Safety Management Addressing Career Knowledge Needs, published in 2003, the following hierarchy of controls was encompassed within The Safety Decision Hierarchy, which is to be discussed later. It may also be found in two articles written by this author Risk Assessment and Hierarchies of Control and Achieving Risk Reduction, Effectively. ... 

In applying The Safety Decision Hierarchy, the goal in the problem identification and analysis phase is to identify and analyze the hazards and assess the risks. Hazard and risk problems cannot be intelligently addressed until the hazards are analyzed and assessments are made of the probability of incidents or exposures occurring and the possible severity of their consequences. Chapter 8, A Primer on Hazard Analysis and Risk Assessment, is a resource for this problem identification and analysis phase. 

When the outcome of a risk assessment indicates that risks are not at an acceptable level, reductions would be achieved through the application of a hierarchy of controls, which is discussed in Chapter 18, Prevention through Design The Standard. ... 

Roles and Responsibilities Top management shall provide the leadership to institute and maintain effective systems for the design and redesign processes. Key points anticipate hazards and risks assess risks apply the hierarchy of controls to achieve acceptable risk levels. The following note is significant in the Roles and... 

Applying the requirements of newly issued or reissued guidelines and standards that propose or require risk assessments and outline a hierarchy of controls to achieve acceptable risk levels such as in the following selection ... 

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