Hazard evaluation, risk assessment

The terminology used varies considerably. Hazard identification and risk assessment are sometimes combined into a general category called hazard evaluation. Risk assessment is sometimes called hazard analysis. A risk assessment procedure that determines probabilities is frequently called probabilistic risk assessment (PRA), whereas a procedure that determines probability and consequences is called quantitative risk analysis (QRA). 

HAZARD IDENTIFICATION RISK ANALYSIS Identify Hazards Evaluate Risks Assess Risks Make Risk-based Decisions Follow Through on Assessment Results Maintain a Dependable Practice... 

In the hazard assessment, it is important to evaluate the toxicological database with regard to its adequacy. The adequacy of a study includes its validity and its relevance. The relevance refers to what has been studied in relation to what is needed for the hazard and risk assessment, and the validity refers to how the study was performed, e.g., conforming with a particular test guideline. The validity and the relevance of a study, or a whole database, has to be considered in relation to the reliability and thus the confidence. The data for hazard assessment are described in detail in Chapter 3. 

It has been suggested to apply an assessment factor for the confidence in the database in case there are limitations in the database, including lack of data for children, which are important in relation to the purpose of the assessment. This section gives an overview of such proposals and evaluations. Then, the key issues are summarized and our recommendations are presented. The question of an extra assessment factor in the hazard and risk assessment for chemicals of concern for children is specifically addressed in Section 5.2.1.13. 

Ku WW, Aubrecht J, Mauthe RJ, et al. Genetic Toxicity Assessment Employing the Best Science for Human Safety Evaluation Part VII Why Not Start with a Single Test A Transformational Alternative to Genotoxicity Hazard and Risk Assessment. Toxicol Sci. 2007 99(l) 20-25. 

Uncertainties. In any hazard or risk assessment it is extremely important that uncertainties be expressed. Frequently the uncertainties are expressed only in statistical terms. It is important that the uncertainties also be expressed in biological terms. Statistical modeling or modeling statistics has become very popular in health risk assessments, particularly for "low dose" extrapolations. As previously stated, there are no mathematical models with a biological basis for reproduction or developmental hazard evaluation. 

Structure-activity relationship (SAR) analysis is essential for the development of pesticides and for the evaluation of cancer hazard and risk assessment. The critical factors that should be considered in SAR analysis and the profile of typical potent carcinogens are discussed. A scheme combining structural and functional criteria for suspecting chemical compounds of carcinogenic activity is presented. Selected classes of pesticides with carcinogenic potential are reviewed to exemplify structural and/or functional features responsible for their carcinogenic activity. 

The Directive defines a system for the classification and categorization of substances according to their hazard potential. Risk assessment, evaluating hazard in the context of quantitative exposure information, is not carried out [3]. Generally, the classification and categorization procedure is conducted by a committee of National Experts who represent Member States. If necessary, a committee of Specialized Experts in a particul field may be convened to review the scientific evidence and attempt to reach a consensus. 

Existing chemical substances, especially those supplied in high volume, may be subject to review in one of the national or international evaluation programs, such as the OECD Screening Information Data Set (SIDS) scheme [7]. Existing data are reported initially, but new studies may be required subsequently to fill data gaps, especially if necessary for adequate assessment of the substance. The hazard and risk assessment could lead to risk management. 

An organization should establish, implement, and maintain procedures for the ongoing hazard identification, risk assessment, risk evaluation, and determination of necessary controls. 

Hazard information is converted to risk information by evaluating the severity of potential accidents associated with the hazard and by evaluating the probability that the hazard could produce an accident. It is done by developing a matrix with severity on one axis and probability on the other, with a numeric code used to represent the risk associated with each hazard. This risk assessment code (RAC) is used to prioritize hazards and determine their acceptability. Hazard severity may be expressed quantitatively (for example, dollar loss or number of injuries), qualitatively (verbal descriptions), or as a combination (Table 11-1). 

Where hazardous chemical(s) are used they should be assessed to determine the impact on the environment. Such an assessment should also consider the effect of intermediates and breakdown products that may be produced. The assessment should include consideration of the effect of the materials on the atmosphere, the sewage treatment system, controlled waters, land and groxmdwater, and waste disposal routes. The risk assessment should include an estimation of the risk from the hazardous materials, the magnitude of the effects, and the probability of an occurrence. Included should be an evaluation of the significance of the hazards and the consequences should the environment be affected. It is a structured approach to setting priorities for controlling the hazards. The risk assessment will provide iiiformation of where control measures will need to be applied to prevent an impact on the environment. 

This is only general guidance. Actual on-site conditions or r ulatory requirements may dictate another hazard evaluation method. A paint inspection by itself may not identify lead-based paint hazards. A risk assessment inspection combination is an option whenever an assessment or inspection is indicated. A risk assessment screen is appropriate for buildings in good condition. Some jurisdications may limit choices in some circumstances. 

Where possible, avoid risks altogether by doing the work a different way without introducing new hazards Evaluate risks that cannot be avoided by risk assessment... 

System safety should be actively involved as a team member in the CM process. All ECPs must be evaluated by an experienced system safety analyst to determine if any hazards are associated with the proposed change, the associated risk, and the safety impact of the ECP on the existing system. The program should be notified when an ECP will decrease the level of safety of the existing system. It is important that only qualified safety engineers make the safety determination on proposed ECPs because they have the most experience and knowledge in regard to system hazards and risk assessments. 

Risk is the safety measure of a potential future event, stated in terms of event likelihood and event severity. Likelihood can be characterized in terms of probability, frequency, or qualitative criteria, while severity can be characterized in terms of death, injury, dollar loss, and so on. Mishap risk analysis is the process of identifying and evaluating the risk presented by a system hazard. HA is an integral part of risk analysis since safety risk can only be determined via the identification of hazards and risk assessment of those identified hazards. See Hazard Risk and Mishap Risk for additional related information. 

Various methods have been introduced to enhance process safety and health performances in the process indnstry. However, most of them were focnsing on evaluating safety and health performance aspects in a proposed process design rather than incorporating those aspects when designing the process. Undonbtedly, hazard and risk assessment is an important element of safety and health management systan—bnt the benefits will be greatest if... 

---