Hazard identification human factor

Hazard Identification - Human Factors and Operational Issues ... 

Hazard identification, step one, means identification of new chemicals or other factors that may cause harmful health effects. Previously, novel hazards were usually observed in case studies or after accidents or other excessive exposures, usually in occupational environments. Today, thorough toxicity studies are required on all pesticides, food additives, and drugs. New chemicals also have to be studied for their potential toxic effects. Thus, earlier hazards were in most cases identified after they had caused harmful effects in humans. Today, most chemical products have been evaluated for their toxicity with experimental animals. Therefore, hazard identification has become a preventive procedure based on safety studies conducted before a chemical compound or product reaches the market, and before individuals are exposed to it. ... 

The final element in management s communication of a desire to reduce human error is the identification and elimination of error-likely situations. Every task is an opportunity for a human error, but some situahons represent greater risks than others. Identifying these high-risk situations is not easy and an expertise in applying human factors principles to the workplace is an essential prerequisite for this identification. Eliminating these hazardous situations is often relatively simple once they have been identified. In some cases it may be appropriate to provide error-tolerant systems, which are those that facilitate identification of and recovery from the errors. 

Management must modify the culture and develop human factors awareness in the hazard identification teams so that they will be capable of identifying the potential for human error. A good practice is to involve operators in the hazard identification team. 

Banks, W., Wells, J. E. (1992). A Probabilistic Risk Assessment Using Human Reliability Analysis Methods. In Proceedings of the International Conference on Hazard Identification and Risk Analysis, Human Factors, and Human Reliability in Process Safety. New York American Institute of Chemical Engineers, CCPS. 

NOAEL (no-observed-adverse-effect level) is defined as the highest dose at which no adverse effects are observed in the most susceptible animal species. The NOAEL is used as a basis for setting human safety standards for acceptable daily intakes (ADIs), taking into account uncertainty factors for extrapolation from animals to humans and inter-individual variabilities of humans. The adequacy of any margin of safety or margin of exposure must consider the nature and quality of the available hazard identification and dose-response data and the reliability and relevance of the exposure estimations. In some cases, no adverse endpoint can be identified such as for many naturally occurring compounds that are widespread in foods. In that case, an ADI Not Specified is assigned. ... 

Opschoor, G., R. O. M. van Loo, and H. J. Pasman. "Methods for Calculation of Damage Resulting From Physical Effects of the Accidental Release of Dangerous Materials." International Conference on Hazard Identification, Risk Analysis, Human Factors and Human Rehabihty in Process Safety, January 15-17, 1992. 

The risk assessment comprises an effect assessment (hazard identification and hazard characterization) and an exposure assessment. The principles for the effect assessment of the active substances are in principle similar to those for existing and new chemicals and are addressed in detail in Chapter 4. Based on the outcome of the effect assessment, an Acceptable Daily Intake (ADI) and an Acceptable Operator Exposure Level (AOEL) are derived, usually from the NOAEL by applying an overall assessment factor addressing differences between experimental effect assessment data (usually from animal studies) and the real human exposure situation, taking into account variability and uncertainty for further details the reader is referred to Chapter 5. As a part of the effect assessment, classification and labeling of the active substance according to the criteria laid down in Directive 67/548/EEC (EEC 1967) is also addressed (Section 2.4.1.8). 

Hazard identification is the process of collecting and evaluating information on the effects of an agent on animal or human health and well-being. In most cases, this involves a careful assessment of the adverse effects and what is the most sensitive population. The dose-response assessment involves evaluation of the relationship between dose and adverse effect. Typically, an effort is made to determine the lowest dose or exposure at which an effect is observed. A comparison is often made between animal data and any human data that might be available. Next is exposure assessment, in which an evaluation of the likely exposure to any given population is assessed. Important parameters include the dose, duration, frequency, and route of exposure. The final step is risk characterization, in which all the above information is synthesized and a judgment made on what is an acceptable level of human exposure. In the simplest terms, risk is the product of two factors hazard and exposure (i.e. hazard x exposure = risk). In real risk assessments, all hazards may not be known and exposure is often difficult to quantify precisely. As a result, the calculated risk may not accurately reflect the real risk. The accuracy of a risk assessment is no better than the data and assumptions upon which it is based. 

As the final step in hazard identification, the risk assessor considers the weight of evidence available from the principal and supporting studies. The results from different studies are examined to determine whether a consistent, plausible picture of toxicity emerges. Some of the factors that add weight to the evidence that the chemical poses a hazard to humans include ... 

Although dose-response assessments for deterministic and stochastic effects are discussed separately in this Report, it should be appreciated that many of the concepts discussed in Section 3.2.1.2 for substances that cause deterministic effects apply to substances that cause stochastic effects as well. The processes of hazard identification, including identification of the critical response, and development of data on dose-response based on studies in humans or animals are common to both types of substances. Based on the dose-response data, a NOAEL or a LOAEL can be established based on the limited ability of any study to detect statistically significant increases in responses in exposed populations compared with controls, even though the dose-response relationship is assumed not to have a threshold. Because of the assumed form of the dose-response relationship, however, NOAEL or LOAEL is not normally used as a point of departure to establish safe levels of exposure to substances causing stochastic effects. This is in contrast to the common practice for substances causing deterministic effects of establishing safe levels of exposure, such as RfDs, based on NOAEL or LOAEL (or the benchmark dose) and the use of safety and uncertainty factors. 

IRIS is a toxicology data file that contains data in support of human health risk assessment. It is compiled by the US EPA and contains over 500 chemical records. IRIS data, focusing on hazard identification and dose-response assessment, are reviewed by work groups of EPA scientists and represents EPA consensus. Among the key data provided in IRIS are EPA carcinogen classifications, unit risks, slope factors, oral reference doses, and inhalation reference concentrations. 

Most short-term tests in bacteria and mammalian cell cultures have been designed primarily for hazard identification and, thus, can represent only the starting point in the process of risk assessment. Whether or not the observed effects are relevant for human exposure depends on bioavailability, absorption, metabofism, half-lives, and other factors that require investigation in vivo. 

As described in a highly referenced document (NRC, 1983), important components of this process include hazard identification, assessment of exposure and dose-response relationships, and characterization of the risk. Uncertainty factors are built into the risk assessment process to account for variations in individual susceptibility, extrapolation of data from studies in laboratory animals to humans (i.e. interspecies variation in toxicokinetics), and extrapolation from high-dose to low-dose exposures. In the case of the association between exposure to chemicals and drugs and autoimmunity or autoimmune diseases, much of the information needed to evaluate risk in the context of the traditional United States National Research Council paradigm is not available. The following represents a discussion of issues in chemical-induced autoimmunity relevant to the use of existing data and data needs in risk assessment. 

International Conference on Hazard Identification and Risk Analysis, Human Factors and Human Reliability in Process Safety... 

In 1990 our understanding of the underlying causes of risk were challenged with the publication of Janies Reason s Human Error [8], For the first time the role of human factors in the incident causality chain were truly characterised. He eloquently made the case for adverse events being a function not of personal inadequacies but of the environment in which individuals operate. This paved the way for transforming a largely reactive approach to risk management in healthcare to one of hazard identification and proactive risk control. 

The hazards identification process must include a review of previous incidents and those near misses which had the potential to create a serious accident. The OSHA standard also identifies administrative issues (such as operating procedures and training) as being an important part of a hazards analysis. In addition, the standard calls for an analysis of siting and human factors. 

H.H. De Jong (2004). Guidelines for the identification of hazards How to make unimaginable hazards imaginable National Aerospace Laboratory NLR, Contract report for Eurocontrol, NLR-CR-2004-094 M.R. Endsley (1995). Towards a theory of situation awareness in dynamic systems. Human Factors, 37(1) 32-64... 

Human Factors and Ergonomics Society Human Immunodeficiency Virus Hazardous Materials Identification System Hazardous Materials Transportation Act... 

Towards human factors methods for SoS hazard identification... 

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