Disasters

Looking back over the last fifty years, it is hard not to associate the chemical industry with serious large-scale accidents. On 10 July 1976, in Seveso, 

a reactor exploded at one of Givaudan-Hoffinan-Laroche s production plants releasing a highly toxic chemical, a dioxin known by its initials TCDD. Thirty-seven thousand people were exposed to this TCDD and 1,800 hectares of this area of Lombardy were contaminated. 

Each industrial accident has provided valuable lessons for industriahsts and public authorities alike. The Seveso dioxin accident, for example, was the reason behind two European directives concerning industrial safety. Nevertheless, chemists know better than anyone else that there is no such thing as zero risk of accidents. The case of the AZF plant in Toulouse demonstrates that even an approved installation boasting a certificate of conformity with ISO norms can explode causing considerable damage. Despite the omnipresence of its products in our daily fives, therefore, chemistry remains a somewhat wild and unpredictable force. The apparently irreducible fact that chemistry poses a threat means that it needs to be strictly supervised and monitored. 

---

The first major hazard in process plants is fire, which is usually regarded as having a disaster potential lower than both explosion or toxic release. However, fire is still a major hazard and can, under the worst conditions, approach explosion in its disaster potential. It may, for example, give rise to toxic fumes. Let us start by examining the important factors in assessing fire as a hazard. 

The second of the major hazards is explosion, which has a disaster potential usually considered to be greater than fire but lower than toxic release. Explosion is a sudden and violent release of energy. 

Vapor cloud explosions. Explosions which occur in the open air are vapor cloud explosions. A vapor cloud explosion is one of the most serious hazards in the process industries. Although a large toxic release may have a greater disaster potential, vapor cloud explosions tend to occur more frequently. Most vapor cloud explosions have been the result of leaks of flashing flammable liquids. 

The third of the major hazards and the one with the greatest disaster potential is the release of toxic chemicals. The hazard posed by toxic release depends not only on the chemical species but also on the conditions of exposure. The high disaster potential from toxic release arises in situations where large numbers of people are briefly exposed to high concentrations of toxic material, i.e., acute exposure. However, the long-term health risks associated with prolonged exposure at low concentrations, i.e., chronic exposure, also present serious hazards. 

The international debt crisis was brought about by Western bankers in search of quick profit and is now one of our most pressing problems. This book looks at the background and shows what we must do to avoid disaster. 

Introduction and commercial application Safety and the environment have become important elements of all parts of the field life cycle, and involve all of the technical and support functions in an oil company. The Piper Alpha disaster in the North Sea in 1988 has resulted in a major change in the approach to management of safety of world-wide oil and gas exploration and production activities. Companies recognise that good safety and environmental management make economic sense and are essential to guaranteeing long term presence in the industry. 

The UK government enquiry into the Piper Alpha disaster in the North Sea in 1988 has had a significant impact on working practices and equipment and has helped to improve offshore safety around the world. One result has been the development of a Safety Management System (SMS) which is a method of integrating work practices, and is a form of quality management system. Major oil companies have each developed their own specific SMS, to suit local environments and modes of operation, but the SMS typically addresses the following areas (recommended by the Cullen Enquiry into the Piper Alpha disaster) ... 

In case of a major disaster, one platform in a region will be equipped to act as a control centre from which rescue operations are co-ordinated. Evacuation routes will be provided, and where large complexes are clustered together, a standby vessel will be available in the region to supply emergency services such as fire fighting and rescue. 

A fatal accident and some other disasters, which were caused by small cracks, lead to a more strict consideration of the security of these steam drums. Parallel to these the economical pressure, due to the globalisation of the today s industry, lead to the increase of the pressure and the rotation speed of the paper production machines for a higher output of the production, which means, that all safety aspects from the design and the material will be exploited totally. On the other hand cast iron is also not a ductile and comfortable material, like the most steels for the pressure equipment. 

On Russia territory there are about 100 thousands of dangerous enterprises and objects, comprising about 1500 nuclear facilities and 3000 chemical and biological extremely hazardous objects. The average period of emergency situations is 10 — 15 years for accidents and disasters with the material loss up to 2 billion USDs, and 15 — 45 days, when the material loss is up to 100 million USDs. 

Yearly the increase of loss due to the accidents and disasters and natural cataclysms is increasing in 10 — 30%. 

Ctillen. The Public Inquiry into The Piper Alpha Disaster (cmliiO)... 

Chemistry, like any scientific discipline, relies heavily on experimental observations, and therefore on data. Until a few years ago, the usual way to publish information on recent scientific developments was to release it in books or journals. In chemistry, the enormous increase in the number of compounds and the data concerning them resulted in increasingly ineffective data-handling, on the side of the producers as well as the users. One way out of this disaster is the electronic processing, by computer methods, of this huge amount of data available in chemistry. Compared with other scientific disciplines that only use text and numbers for data transfer, chemistry has an additional, special challenge molecules. The molecular species consist of atoms and bonds that hold them together. Moreover, compounds... 

If we compare the calculated total ionization potential, IP = 4.00 hartiees, with the experimental value, IP = 2.904 hartiees, the result is quite poor. The magnitude of the disaster is even more obvious if we subtract the known second ionization potential, IP2 = 2.00, from the total IP to find t c first ionization potential, IPi. The calculated value of IP2, the second step in reaction (8-21) is IP2 = Z /2 = 2.00, which is an exact result because the second ionization is a one-election problem. For the first step in reaction (8-21), IPi (calculated) = 2.00 and IPi(experimental) = 2.904 — 2.000 =. 904 hartiees, so the calculation is more than 100% in error. Clearly, we cannot ignore interelectronic repulsion. 

The pubhc perceives the risk of nuclear power to be much greater than that deterrnined by experts (4). Among explanations for the discrepancy are the behef in the possibiUty of a disaster and the association of reactors with weapons. Living 50 years within five miles of a nuclear power plant has been shown to be comparable in terms of risk to smoking 1.4 cigarettes during the same period (5). 

Devastation caused by pests has troubled both ancient and modem humans often changing the course of history. The bubonic plague in Europe and the great potato famine in Ireland were both caused by pests. In 1884, grasshoppers caused such a food shortage in the midwestem United States that a national disaster was declared. 

In Delaware, the Regulation for the Management of Extremely Ha2ardous Substances Act, developed in response to the Bhopal disaster and several chemical-release incidents in Delaware, became effective in 1989 (27,28). The regulations Hst 88 toxic substances, 32 flammable substances, and 50 explosive substances. A sufficient quantity is specified for each of these materials, based on potential for a catastrophic event at a distance of 100 m from a potential source of a 1-h release. 

The state of Texas controls chemical process ha2ards through its statute that estabUshed the Texas Air Control Board in 1965. In 1985, guidelines were estabUshed for evaluations of community impact of releases of 46 toxic chemicals, if Texas decides that a disaster potential exists (26). 

Protection of Employees. In 1986, shortly after the Bhopal disaster, OSHA contracted to develop a federal standard on process ha2ards management. A proposed standard was issued in 1990, and the Process Safety Management of Highly Ha2ardous Chemicals standard was issued and implemented in 1992 (36). 

Disaster Planning. Plant managers should recogni2e the possibiHty of natural and industrial emergencies and should oversee formulation of a plan of action in case of disaster. The plan should be weU documented and be made known to all personnel critical to its implementation. Practice fire and explosion drills should be carried out to make sure that all personnel, ie, employees, visitors, constmction workers, contractors, vendors, etc, are accounted for, and that the participants know what to do in a major emergency. 

Storage Facilities The Fhxborough disaster (Lees, 1980) occurred on June I, 1974, and involved a large, unconfined vapor cloud explosion (or explosions—there may have been two) and Fire that killed 28 people and injured 36 at the plant and many more in the surrounding area. The entire chemical plant was demolished and 1821 houses and 167 shops were damaged. 

The results of the Flixborough investigation made it clear that the large inventory of flammable material in the process plant contributed to the scale of the disaster. It was concluded that limitations of inventory should be taken as specific design objectives in major hazard installations. It should be noted, however, that reduction of inventoiy may require more frequent and smaller shipments and improved management. 

NFPA 1600 Recommended Practice for Disaster Management, 1995 edition. National Fire Protection Association, Quincy, MA. 

---