Safety Seveso incident

The first safety cases prepared for the process industries were those developed for North Sea offshore oil and gas operations following the Piper Alpha disaster that occurred in the year 1988. The Cullen report (Cullen, 1990) that was written following that accident was highly critical of offshore operating practices and recommended that a safety case approach be implemented. The Seveso incident that occurred in Italy further prompted the increased use of safety cases. Since that time the use of safety cases has spread to other industries (such as mining and railway operations) and to other nations, primarily in Europe and Australasia. (It is notable that the safety case regime approach has not been taken up for offshore oil and gas operations in the Gulf of Mexico—instead a more prescriptive approach based on industry consensus standards is used.)... 

A publication summarises all the then available technical evidence related to the Seveso accident, and recommends operational criteria to ensure safety in commercial processes to produce trichlorophenol [4], All the plant scale incidents were characterised [ 1 ] by the subsequent occurrence of chloracne arising from the extremely toxic and dermatitic compound 2,3,7,8-tetrachlorodibenzodioxin (structure IX, p. S-3), formed dining the thermal runaway reaction and dispersed in the ensuing explosion. It is also extremely resistant to normal chemical decontamination procedures, and after the 1968 explosion, further cases occurred after transient contact with plant... 

Lodi, New Jersey incident, 8, 159-160 management practices, 67-68 Paterson, New Jersey incident, 160-161 Seveso, Italy incident, 4 Springfield, Massachusetts incident, 7 Toulouse, France incident, 4,5 Castleford, UK incident, 11,156-158 Center for Chemical Process Safety (CCPS), 183... 

The Seveso accident in 1976 also involved the glycol-based process, but differed fundamentally from the 1968 incident. While the latter apparently involved a thermal runaway initiated during the hydrolysis reaction by application of excessive heat by the faulty hot oil system [7], the process design adopted by Icmesa at Seveso featured heating the reaction vessel by steam at 12 bar (192°C if saturated) to ensure a minimum 40°C safety margin below the known decomposition temperature of 230°C [5]. At Seveso the exothermic hydrolysis reaction had been completed, but... 

Most credible initiating events and their fi equencies can be gathered either from the company s incidents library or from agencies such as CSB (Chemical Safety Board in US), CIMAH (Control of Industrial Major Accident Hazards in US), COMAH (Control of Major Accident Hazards in UK), European Seveso H Directive and HSE (Health and Safety Executive in UK). 

The Flixborough nylon plant accident in the UK (1974) was caused by an open-air explosion of a flammable gas released into the air. It killed the 28 plant employees present and caused extensive property damage in the surrounding area. The failure to perform a full technical assessment of a modification was given as the main cause of the event. The Seveso pesticide plant accident in Italy (1976) is well known for the dangerous release of dioxin due to poor plant safety features and to the underestimation of the possibility of a runaway reaction. The Bhopal incident in India (1984), at another pesticide plant, killed an estimated 4000 (although the total number is still unknown). This disaster was attributed to too large an inventory of toxic substances and to very poor staff attention to the operability of safety features. 

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