Factors concerning humans

Despite the lack of interest in human factors issues in the CPI in the past, the situation is now changing. In 1985, Trevor Kletz published his landmark book on human error in the CPI An Engineer s View of Human Error (revised in 1991). Several other books by the same author e.g., Kletz (1994b) have also addressed the issue of human factors in case studies. Two other publications have also been concerned specifically with human factors in the process industry Lorenzo (1990) was commissioned by the Chemical Manufacturers Association in the USA, and Mill (1992), published by the U.K. Institution of Chemical Engineers. In 1992, CCPS and other organizations sponsored a conference on Human Factors and Human Reliability in Process Safety (CCPS, 1992c). This was further evidence of the growing interest in the topic within the CPI. 

The last area addressed by the systems approach is concerned with global issues involving the influence of organizational factors on human error. The major issues in this area are discussed in Chapter 2, Section 7. The two major perspectives that need to be considered as part of an error reduction program are the creation of an appropriate safety culture and the inclusion of human error reduction within safety management policies. 

Record those factors, both human and system-based, that were analyzed and found not to be relevant. For example, concern frequently centers on personnel competency issues, and if this is not a factor in the incident, it should be stated. Other noncontributory factors should also be recorded. 

Another possible dietary factor concerns the essential fatty acid content of human and artificial milk. It has been postulated by Sinclair that many modern dietaries are deficient in the essential polyethenoid fatty acids (EFA) and that in consequence there is a rise in unesterified (and more active) vitamin D and in unesterified cholesterol. He has suggested that a part of the etiology of infantile idiopathic hypercalcemia may be attributed to EFA deficiency (S5). He has pointed to the lower content of certain unsaturated fatty acids in cow s milk as compared with human milk as a factor in the development of idiopathic hypercalcemia in artificially fed infants. He considers that dried milk has an even lower content of essential fatty acids than liquid cow s milk and that the longer it is stored the lower does the essential fatty acid content become. On the basis of some observations on rats, he suggests that a dietary deficiency of the essential fatty acids increases susceptibility to the possible toxic effects of vitamin D. The age of the rats, the duration of the essential fatty acid deficient diet, or the dosage of vitamin D is not mentioned, and there would appear to be no other experimental data to support these views. 

Snicide deaths and impnlsive acts of self-harm associated with pesticides have cansed increasing global concern. It has been reported that deliberate ingestion associated with pesticides has resnlted in 2-3 million hospital admissions and about 220,000 deaths each year. In recent years, pesticides have been used in a spate of suicides in some parts of India (Andhra Pradesh). Pest resistance and resurgence (mainly on cotton crops) and abuse of pesticides because of lack of strict market regulation of toxic chemicals like pesticides have been found to be the causative factors of human poisonings. 

Failure sequence modeling techniques such as fault tree analysis or event tree analysis are used to estimate die likelihood of incidents in facilities where historical data is unavailable, or is inadequate to accurately estimate die likelihood of the liazardous incidents of concern. Odier modeling tecluiiques may be required to consider die impact of external events (eardiquakes, floods, etc.), common cause failures, and liunian factors and human reliability. 

Actually, there are sound scientific explanations of why firewalking is possible. The first important factor concerns the heat capacity of feet. Because human tissue is mainly composed of water, it has a relatively large specific heat capacity. This means that a large amount of energy must be transferred from the coals to significantly change the temperature of the feet. During the brief contact between... 

The prediction of errors is considered an important human factor concern (Wickens, 1990). Numerous experimental studies show that SP and performance parameters correlate significantly, where higher SP negativity indicates better performanee. Because SP negativity precedes the overt behavior and per-... 

DOE Order 5480.23, Nuclear Safety Analysis Reports (DOE 1994a), Paragraph 8b(3)(n), as amplified by Attachment 1, Paragraph 4f(3)(d)14, of the order (Topic 14) requires a systematic inquiry into or evaluation of human factors for the facility. DOE Memorandum, Safety Analysis Report Guidance - Human Factors, DOE/DP-625 (DOE 1992), indicates that the use of the Human Factors Safety Analysis checklist will satisfy the requirements of DOE Order 5480.23 concerning human factors for existing facilities. 

Verification the process of determining whether the quahty or performance of a product or service is as stated, as intended or as required. Verification is closely related to quahty assurance and quality control. It is the evaluation performed to confirm the correctness of a written procedure or guidehne to ensure that technical and human factor concerns have been properly incorporated. EOF verification The objective of EOF verification is to determine that consistency has been maintained between the EOFs and the EOF source documents. Consistency is determined by verification principles of written correctness and technical accuracy. Written correctness ensures that information is incorporated as specified by administrative guidance. Technical accuracy ensures proper incorporation of generic and plant specific technical information. 

A second significant factor concerns both the relative amounts of environmental media contamination from lead and the relative amounts of the medium contacted by exposed populations. Both lead intake scenarios can be important, as seen in the next chapter on human exposures. A third broad characteristic has to do with the physical, chemical, physicochemical, and geochemical nature of the element present in some medium. These characteristics affect the extent to which lead levels in some medium are absorbed into the bloodstream. 

Since PRA by that time had become established as the industry standard for how to deal with the safety and reliability of technical systems, it was also the natural starting point when the human factor needed to be addressed. Extending PRA to include human factors concerns led to the development of a number of methods for Human Reliability Assessment (HRA). At first, the... 

Ikeda, T. Human Factors Concerning Drivers of High-Speed Passenger Trains. Rail International, no. 3 (1995) 19-24. 

The GPCA safety requirements were designed on the basis of a preliminary hazard analysis for the controller of the pump. We found that almost half of the requirements can be related to user interface functionalities, and correctly capture basic human factors concerns. However, a hazard analysis specifically addressing user interface functionalities is needed to cover a more complete set of aspects related to human factors. We are currently starting this hazard analysis. Some examples of safety features and constraints that are currently not considered in the GPCA safety requirements and can potentially make the user interface design safer follows. 

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