Accident causes

The accident at the Three Mile Island (TMI) plant in Pennsylvania in 1979 led to many safety and environmental improvements (4—6). No harm from radiation resulted to TMI workers, to the pubHc, or to the environment (7,8), although the accident caused the loss of a 2 x 10 investment. The accident at the Chernobyl plant in the Ukraine in 1986, on the other hand, caused the deaths of 31 workers from high doses of radiation, increased the chance of cancer later in life for thousands of people, and led to radioactive contamination of large areas. This latter accident was unique to Soviet-sponsored nuclear power. The Soviet-designed Chemobyl-type reactors did not have the intrinsic protection against a mnaway power excursion that is requited in the test of the world, not was there a containment building (9—11). 

This chapter describes accidents caused by those slips and lapses of attention that even well-trained and well-motivated persons make from time to time. For example, they forget to close a valve or close the wrong valve. They know what they should do, want to do it, and are physically and mentally capable of doing it. But they forget to do it. Exhortation, punishment, or further training will have no effect. We must either accept an occasional error or change the work situation so as to remove the opportunities for error or to make errors less likely. 

ACCIDENTS CAUSED BY SIMPLE SLIPS. TO PREVENT THEM WE SHOULD CHANGE THE PLANT DESIGN OR METHOD OF WORKING. 

On January 4, 1966, at Feyzin refinery in France, a leak from a propane storage sphere ignited. The fire burned around the vessel and led to boiling liquid expanding vapor explosions. The accident caused eighteen deaths and eighty-one injuries. 

The Systems Approach emphasizes the value of near-misses as a rich source of information about accident causes. This is based on the concept of accidents... 

Chapter 14 Introduction to Hazard Risk Assessiiiciit Chapter 15 Evcnt/Haaird Identification Chapter 16 Accident Causes and Probability Chapter 17 Accident Consequences and Evaluation Chapter 18 Hazard Risk Analysis... 

The e.xamples of accidents caused by human error discussed below are described in detail by Kletz... 

Accident caused when using a solution at 15% of nitric acid in ethanol. These concentrations should never exceed 10%. These concentration effects are due to an inversion in the order in which reagents should be incorporated. 

There have been a lot of accidents caused by the ignition of ammonia in oxygen. If ammonia is in the liquid state, the mixture can instantaneously detonate. 

There was also the case of an accident caused by the explosion of a container due to overpressure. An aluminium chloride odium peroxide/powdered aluminium mixture in the container was kept like this for 41 days. Note that these three elements represent great deinger when water is present. 

Liittgens, G., Collection of accidents caused by static electricity, J. Electrostatics, 16 247-255 (1985)... 

Use the Flixborough Works accident and the investigation developed in Problem 12-1 to develop an investigation summary similar to Example 12-2. Include layered recommendations to cover the accident causes and underlying causes. 

Accident statistics on the equipment involved in large losses give somewhat contradictory information (see Table 20). According to Mahoney (1992) the most common process items as primary accident cause are reactors. The next in the list are process drums whereas heaters are one of the safest. This contrasts with Instone s (1989) data, where heaters and boilers were the most common process items in the accidents, whereas reactors and process drums were quite uncommonly involved. This difference may be partly because Mahoney has analyzed the primary causes of large losses, whereas Instone has listed the involvement of equipment in losses. Since furnaces are sources of ignition for flammable leaks from other equipment, furnaces are not necessarily listed as primary causes even they are probably involved as secondary causes in many losses. Therefore the inclusion of both reactors and furnaces in the list of most unsafe equipment is well justified. 

In a brief review of chemical accidents caused by accidental contamination of process materials, attention is drawn to the much less frequent opposite effect of accidental decontamination (or purification) as a cause of accidents. Some examples of the effects arising from accidental loss or inactivation of stabilisers or antioxidants from reactive materials are given. 

With the widening availability and industrial use of oxygen, accidents caused by atmospheric enrichment have increased. Most materials, especially clothing, bum... 

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