Severity of risk

While the Act specifies no criteria for measuring the severity of risk, two considerations seem logically relevant. First, what is the probability that the product defect will in fact injure consumers In other words, what fraction of the consumers who are exposed to the product will be injured Second, in those cases where the product will cause injury, what type of injury will occur Will that injury be death, serious bodily harm or merely minor injury In applying these considerations to specific products, the product s historical safety record will undoubtedly be relevant, as will an analysis of the conditions which must be present in order for the product defect to result in injury. In the latter con-... 

From the preceding discussions, it is clear that risk level is a quantitative expression of severity of risk, and can be found by combination of likelihood and consequence, and it is embedded in the risk matrix. So it is not possible to directly measure, hut can he referenced after constructing a specific risk matrix. Normally it is expressed in terms of low, medium, high, very high, and extreme. Usually more than five discrete levels of risk have no practical application. So negligible or very low are not considered. In Table 1/3.3.3-1, various risk levels and associated actions has been depicted to show importance of risk level. 

All human actions involve some level of risk as they are engaged in thousands of daily at-risk events. Think about what you do on a daily basis Try to become aware and notice the level and severity of risk that you actually accept for yourself and others. For example, driving on a major highway, moving from one lane to another in heavy traffic while on a cell phone, eating, or engaged in passenger conversation. 

Be conducted at regular intervals. The frequency depends on the potential hazards and severity of risks. 

Cause effect matrix The cause and effect matrix or XY matrix (not to be confused with the fishbone diagram) is used to quantify how significantly each input may affect the desired output (The Process Improvement Notebook,TQLO Publication No. 97-01, n.d.). An overview of the XY matrix is provided for an overview of the process of categorizing and comparing the probability and the severity of risk. Severity and probability potential hazards use a different format shown in Chapter 8 (The Process Improvement Notebook, TQLO Publication No. 97-01, n.d.). 

The most popular scheme among commercial companies is the assignment of a risk priority number (RPN) based on probabiUty of occurrence, detectabihty, and severity of a particular failure mode. The factors (Occ, Sev, and Det) are each rated on a 1 to 10 scale and then an RPN is based on the product of the three rating values. 

Initially, the source of environmental risk from cooling water was assumed to be the pollutant discharged, ie, heat, in the form of the elevated temperature of the water released from the condensers. Heat is now recognized as being only one of several potential risks of power station cooling (Fig. 2). 

Risk analysis is the process of gathering data and synthesizing information to develop an understanding of the risk of a particular enterprise. Risk analysis usually involves several of the five risk management activities shown in Figure 1. CPI companies have many possible applications... 

Another way to evaluate risks is to calculate the sensitivity of the total risk estimates to changes in assumptions, frequencies, or consequences. Risk analysts tend to be conservative in their assumptions and calculations, and the cumulative effect of this conservatism may be a substantial overestimation of risk. For example, always assuming that short-term exposure to chemical concentrations above some threshold limit value will cause serious injury may severely skew the calculated risks of health effects. If you do not understand the sensitivity of the risk results to this conservative assumption, you may misallocate your loss prevention resources or misinform your company or the public about the actual risk. 

We can demonstrate the notions of risk and risk assessment using Figure 1.18. For a given probability of failure occurrence and severity of consequence, it is possible to map the general relationship of risk and what this means in terms of the action required to eliminate the risk. 

For example, if both occurrence and severity are low, the risk is low, and little or no action in eliminating or accommodating the risk is recommended. ITowever, for the same level of occurrence but a high severity, a medium level of risk can be associated with concern in some situations. The level of occurrence, for some unknown reason, changes from low to medium and suddenly we are in a situation where the risk requires priority action to be eliminated or accommodated in the product. 

The doeumentation of the risks for eaeh eomponent and assembly operation follows the determination of the assembly sequenee diagram, if appropriate, when the produet eonsists of more than a single eomponent. Every eritieal eomponent eharaeteristie or assembly stage is analysed through the use of the variability risks table. An assembly risk analysis will be performed during several of the ease studies presented later. 

All minor cuts should be cleaned thoroughly and covered with a suitable dressing. After controlling bleeding, if there is a risk of a foreign body in the wound do not attempt to remove it, but cover loosely and take patient to a doctor or hospital, as should be done if there is any doubt about the severity of the wound. 

Objective Provide a basis to judge the relative likelihood (probability) and severity of various possible events. Risks can be expressed in qualitative terms (high, medium, low) based on subjective, common-sense evaluations, or in quantitative terms (numerical and statistical calculations). 

The physical condition and characteristics of the material shipped should be considered in transportation risk assessments on a case-by-case basis. There may be options available to reduce transportation risk by reducing the potential for releases or the severity of the effects of releases. A few possible ways of improving safety by modifying conditions are ... 

To conclude, this sampling of the literature of risk perception, the comments of Covello, 1981 may be summarized. Surveys have been of small specialized groups - generally not representative of the population as a whole. There has been little attempt to analyze the effects of ethnicity, religion, sex, region age, occupation and other variables that may affect risk perception. People respond to surveys with the first thing that comes to mind and tend to stick to this answer. They provide an answer to any question asked even when they have no opinion, do not understand the question or have inconsistent beliefs. Surveys are influenced by the order of questions, speed of response, whether a verbal or numerical respon.se is required and by how the answer is posed. Few Studies have examined the relationships between perceptions of technological hazards and behavior which seems to be influenced by several factors such as positive identification with a leader, efficacy of social and action, physical proximity to arenas of social conflict. 

The mechanisms behind the different types of risks are also quite varied, because manufacturers may apply different conditions and agents, and each manufacturing stage may involve different job functions and therefore different exposure conditions. Distance to emission sources and physical parameters such as rate of release, air currents, and meteorological variations have a profound influence. The variability of exposure conditions is made even greater by work patterns, individual practices, and simultaneous exposure to several substances acting together. 

Risk is often defined as the likelihood of a certain event times a measure of the severity of its consequences. Most risk assessment studies concentrate on estimating the likelihood of certain events. They often concern the release of chemicals, or accidents in engineering projects and the project outcome. In thi.s section, the subject of accidents is not covered. Risk assessment (RA), as a technique, has been adopted by various national governments, by EU, and by OECD.-... 

The corrective action requirements fail to stipulate when corrective action should be taken except to say that they shall be to a degree appropriate to the risks encountered. There is no compulsion for the supplier to correct nonconformities before repeat production or shipment of subsequent product. However, immediate correction is not always practical. You should base the timing of your corrective action on the severity of the nonconformities. All nonconformities are costly to the business, but correction also adds to the cost and should be matched to the benefits it will accrue (see later under Risks). Any action taken to eliminate a nonconformity before the customer receives the product or service could be considered a preventive action. By this definition, final inspection is a preventive action because it should prevent the supply of nonconforming product to the customer. However, an error becomes a nonconformity when detected at any acceptance stage in the process, as indicated in clause 4.12 of the standard. Therefore an action taken to eliminate a potential nonconformity prior to an acceptance stage is a preventive action. This rules out any inspection stages as being preventive action measures - they are detection measures only. 

Furthermore, once every process component has been analyzed separately for worst case, stand-alone conditions, there is no additional safety risk created by joining the components into a system. That is, if every process component is fully protected based on its FMEA analysis, a y tern made up of several of these components will also be fully protected,... 

It is important to remember that unexpected benefits may arise from integration. You should actively look for these benefits and document them. It may be possible to improve some of these benefits by small modifications to the plan or integration framework. Such additional work should be undertaken only with the appropriate approvals. Never the less, if any benefits would only be achieved with the integration project, you should include them in your overall statement of benefits. An example of this might be the better allocation of capital to risk reduction efforts when an integrated risk assessment is done-addressing several different types of risk. 

The Chemical Process Industry (CPI) uses various quantitative and qualitative techniques to assess the reliability and risk of process equipment, process systems, and chemical manufacturing operations. These techniques identify the interactions of equipment, systems, and persons that have potentially undesirable consequences. In the case of reliability analyses, the undesirable consequences (e.g., plant shutdown, excessive downtime, or production of off-specification product) are those incidents which reduce system profitability through loss of production and increased maintenance costs. In the case of risk analyses, the primary concerns are human injuries, environmental impacts, and system damage caused by occurrence of fires, explosions, toxic material releases, and related hazards. Quantification of risk in terms of the severity of the consequences and the likelihood of occurrence provides the manager of the system with an important decisionmaking tool. By using the results of a quantitative risk analysis, we are better able to answer such questions as, Which of several candidate systems poses the least risk Are risk reduction modifications necessary and What modifications would be most effective in reducing risk ... 

Reliability Data Collection and Use in Risk and Availability Assessment Varied 72 papers, several of which contain some data Wide variety of systems and components 48. 

Risk iuialysis of accidents serves a dual purpose. It estimates tlie probability tliat iui accident will occur and also assesses the severity of the consequences of an accident. Consequences may include dmnage to tlie surrounding enviromnent, financial loss, injury to life and/or deatli. This Part of the book (Part IV) is primarily concerned witli tlie metliods used to identify liazards and causes and consequences of accidents. Issues dealing witli healtli risks have been explored in die previous Part (III). Risk assessment of accidents provides an effective way to help ensure eidier diat a mishap will not occur or reduces the likelihood of an accident. The result of die risk assessment also allows concerned parties to take precautions to prevent an accident before it happens. 

If the probability of the accident and tlie severity of its consequences are low, then die risk is usually deemed acceptable and the plant should be allowed to operate. If die probability of occurrence is too high or die damage to the surroundings is too great, dien the risk is usually unacceptable and die system needs to be modified to minimize these defects. 

Risk assessment of accidents estimates tlie probability that hazardous materials will be released and also assesses the severity of the consequences of an accident. 

---