**5. Dealing with knowledge during risk assessment**

Normally, scientific risk assessment should be performed before labeling any event as "risky." Identification of a hazard is the first step in the risk assessment process. Before identifying the hazard, potential disease or outcome clusters need to be found. For example, before 1989 only one disease outbreak per year was identified in a population of over 60 million people in the Philippines. A surveillance system was set up in 1989 and in 1995 more than 80 disease outbreaks were identified [10]. This means that risks cannot be described as such unless there are procedures to identify or measure outcome clusters or hazards (perceived or real) and our vulnerability to them. Another point worth mentioning is that if you do not know the hazard, you cannot perceive the related risk. The second stage of the risk assessment process entails an estimate of the associated level and extent of potential harm which together with the expected probability of an unwanted event are important, because the evaluation of the acceptability of the options for mitigating the identified risk will usually depend on how much harm the hazard we identify can be estimated to make. For the assessment procedure, two forms of assessment are discussed in detail: the technical procedure and the observational approach.

In the technical procedure like *engineering*, material properties, technical performances, or technical measurements are based on tests or experiments. The results are countable from numerous versions of repeated experiments. The experimental approach allows estimating a small confidence interval considering probabilistic calculations. One example is the overall construction procedure in the design of the roof for a building. First, the total design load on the roof must be computed. The different loads could typically be: self‐weight, wind load, and snow load. A design load can then be computed as the sum of these loads. However, as the loads are stochastic in nature, each load is multiplied by a coefficient that accounts for the lower probability that all loads are maximal at the same time. Strengthening the construction is intended to reduce the risk of failure, but will never eliminate it, and the design of a construction is, therefore, a balance between strength and acceptable risk for failure.

In the observational approaches of *epidemiological and public health* studies, the outcomes of interest are often death or diseases like cancer, myocardial infarction, or infectious diseases. There may be several causes for having that outcome and several hazards may need to be considered for the risk assessment. One cause hardly ever leads to only one single outcome. Stress at work, for example, is a risk factor for myocardial infarction. But other risk factors like hypertension, overweight, unhealthy blood lipid profile, or lack of physical activity are also risk factors for myocardial infarction and all of them may be related to stress at work. On the other hand, overweight has more than one adverse consequence, including a higher risk of some cancers or diabetes. The complexity is topped by the inherent and much higher heterogeneity in susceptibility to an adverse outcome in a population of humans than among construction parts in engineering. Risk assessment is still possible; and for the quantitative estimation of absolute or relative risk, epidemiological measures are used by calculating disease rate and comparing rates of exposed and unexposed groups [11].

impact on life and of reversibility. The assessment of severity is a quantitative part of hazard evaluation, and the subjective acceptance is the qualitative part. It is subjective because it is

On the basis of these facts, a dichotomous hazard will be transformed into a quantitative risk term [9]. In all disciplines, there are two most known concepts of risk definition: the probability of occurrence and severity of the undesirable outcome. Under this approach, risk is the probability function that reflects in quantitative terms the likelihood that a hazard manifests

Normally, scientific risk assessment should be performed before labeling any event as "risky." Identification of a hazard is the first step in the risk assessment process. Before identifying the hazard, potential disease or outcome clusters need to be found. For example, before 1989 only one disease outbreak per year was identified in a population of over 60 million people in the Philippines. A surveillance system was set up in 1989 and in 1995 more than 80 disease outbreaks were identified [10]. This means that risks cannot be described as such unless there are procedures to identify or measure outcome clusters or hazards (perceived or real) and our vulnerability to them. Another point worth mentioning is that if you do not know the hazard, you cannot perceive the related risk. The second stage of the risk assessment process entails an estimate of the associated level and extent of potential harm which together with the expected probability of an unwanted event are important, because the evaluation of the acceptability of the options for mitigating the identified risk will usually depend on how much harm the hazard we identify can be estimated to make. For the assessment procedure, two forms of assessment are discussed in detail: the technical procedure and the observa-

In the technical procedure like *engineering*, material properties, technical performances, or technical measurements are based on tests or experiments. The results are countable from numerous versions of repeated experiments. The experimental approach allows estimating a small confidence interval considering probabilistic calculations. One example is the overall construction procedure in the design of the roof for a building. First, the total design load on the roof must be computed. The different loads could typically be: self‐weight, wind load, and snow load. A design load can then be computed as the sum of these loads. However, as the loads are stochastic in nature, each load is multiplied by a coefficient that accounts for the lower probability that all loads are maximal at the same time. Strengthening the construction is intended to reduce the risk of failure, but will never eliminate it, and the design of a con-

In the observational approaches of *epidemiological and public health* studies, the outcomes of interest are often death or diseases like cancer, myocardial infarction, or infectious diseases. There may be several causes for having that outcome and several hazards may need to be considered for the risk assessment. One cause hardly ever leads to only one single outcome. Stress at work, for example, is a risk factor for myocardial infarction. But other risk factors like hypertension, overweight, unhealthy blood lipid profile, or lack of physical activity are

struction is, therefore, a balance between strength and acceptable risk for failure.

the individual's own judgment reflecting their values and preferences.

256 Knowledge Management Strategies and Applications

**5. Dealing with knowledge during risk assessment**

tional approach.

itself while as we have alluded to earlier, the undesirable outcome is the hazard.

Risk assessment in *occupational health* is traditionally based on a four‐stage process: hazard identification, exposure assessment, dose‐response assessment, and risk characterization. However, risk assessment is typically put into the broader context of managing occupational risks and often includes ongoing monitoring and evaluation of the effectiveness of any initiative to decrease risk to an acceptable level. An acceptable risk level is defined not solely by health arguments but, especially in the case of carcinogenic agents that have stochastic health effects, such as hexavalent chromium exposure in electroplating causing lung cancer, also includes considerations on financial and technical feasibility. Since the main reason of risk assessment is to determine what, if any, measures should be taken by the employer to prevent adverse health effects in workers, it is common to integrate risk assessment and risk management in occupational health practice [12, 13]. Occupational health and safety is, therefore, one of the most regulated areas in terms of legal requirements for risk assessment [14].

Medical and environmental risk assessments to guide risk management become increasingly challenging, when certain exposures have both risks and benefits, or when the hazard is intended or inherent in a specific scenario. Medical application is a common example of balancing benefit and harm. The use of computed tomography (CT) with its high resolution can clearly lead to better diagnosis and planning of treatment and then becomes lifesaving, but given its exposure to ionizing radiation, a well‐known carcinogen, endorses recommendations that unnecessary examinations need to be avoided and optimal dose adjustment, for example for children, is to be applied [15]. However, there may clearly be a huge risk related to avoiding the hazard of undergoing a CT examination, for instance, due to a delayed detection of cancer. Also, in environmental health not all hazards are entirely avoidable, but risk assessment can guide policy decisions insofar as where to set priorities for an acceptable level of risk and of how much risks can be reduced.
