Export Inherent Safety NOT Risk

David W. Edwards, Visiting Fellow, Department of Chemical Engineering, Loughborough University, LOUGHBOROUGH, LE11 3TU, UK. [email protected]

ABSTRACT

The author presents a personal view that production of bulk chemicals and the attendant risks are being transferred from developed to developing nations. Some evidence is presented for the transfer of production. The transferred risk is increased because of the larger scale plants that are now built in locales that are less able to cope with the increased hazards. Bhopal was an example of an inherently unsafe plant, with major hazards that could have been avoided or drastically reduced by design. It behoves the industry to adopt the inherently safer philosophy and practice in the new plants that it builds, in order to minimise the opportunity for another accident like Bhopal and the threat to our industry that such an accident would pose.

KEYWORDS

Bhopal, chemicals production, risk transfer, inherent safety

INTRODUCTION

This paper presents a personal view about the current development of the chemical industry, with increased-scale bulk chemicals production appearing to be transferred from developed to developing countries and with it the attendant risks to people and the environment. I believe that this export of risk is neither ethical nor good business. Furthermore, it would not happen if we build inherently safer plants that avoid or minimise the hazards.

The release of toxic gas at Bhopal remains the world’s worst industrial accident, which immediately killed any number of people from about 2000 to 8000 (depending upon your information source). The toxic gas was emitted from a chemical plant that was built and operated in a developing country by a chemical company from the developed world.

Union Carbide Corporation (UCC) and their new owners, the Dow Chemical Company, argue that it was Union Carbide India Limited (UCIL) that owned and operated the Bhopal plant. However, as reported on their own website1, UCC owned 50.9 percent of UCIL. My arithmetic says that 50.9% is greater than 50% and therefore represents a controlling interest, which means that UCC bore ultimate responsibility for the plant.

The Bhopal accident should be an awful warning of what can happen when dangerous chemicals are produced with less care than ought to be exercised in a populous developing country location. However, as Gupta noted in a recent editorial in Process Safety and Environmental Protection2, we seem to be doing our best to forget that it ever happened.

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Bhopal and Inherent Safety, Hazard and Risk

The agent that caused the deaths and injuries at Bhopal was methyl isocyanate (MIC). An unintended reaction caused it to be released from a large storage tank containing 40 tonnes. However, the MIC was neither a raw material nor a finished product, which might have justified such storage, but it was an intermediate in a sequence of reaction and process steps. As such it should not have been stored and certainly not stored in such large quantities. Furthermore, there is an alternative way of making the final product, carbaryl, which uses the same raw materials as the Bhopal plant3. These same feedstocks are reacted in a different order and MIC is not produced, see figure 1. If this ‘reaction route’ had been used at Bhopal, there would have been no MIC intermediate to escape and kill and maim so many people. Thus on a number of counts the Bhopal plant was inherently unsafe – choice of reaction route and storage of large quantity of hazardous material being just two. When the systems, or so-called layers of protection, in place on the plant to control or mitigate the MIC hazard were called upon to act they were either ineffective, disabled or failed. The conventional approach to ensure acceptable plant safety by reducing risk did not work.

Although there are many definitions, I shall use the following definitions of hazard and risk that are widely used in the process industries4. Hazard - a physical situation with potential for human injury, damage to property, damage to the environment or some combination of these. Risk – the likelihood of a specified undesired event occurring within a specified period or in specified circumstances. It may be either a frequency (the number of specified events occurring in unit time) or a probability (the probability of a specified event following a prior event), depending on the circumstances. In an inherently safeR (nothing can ever be absolutely safe) plant the hazards are identified early and avoided or minimised by design. Therefore, an inherently safer plant design usually minimises risk as well. Conventional plant design accepts some hazards. Added protective systems reduce the risk of realisation of these hazards to an acceptable level. Mitigating systems reduce the severity of the consequences of realisations.

A good Indian example of inherent safety is the bungalow. Bungalows are inherently safer than houses, because they do not have stairs, which are the major cause of serious accidents in the home. Stairs are inherently unsafe, but they may be made safe by lighting, fitting a handrail and child-gates, etc. It is important to distinguish between inherent safety and safety (the Bhopal plant was safe when built and operated correctly), because inherent safety is the more desirable quality. It is better to achieve safety inherently (live without stairs in a bungalow) rather than by modification (fitting a handrail, etc), because then unexpected events (for example a rotten treadboard or childrens’ roller skates, etc), whether foreseen or not, cannot cause a problem. However, inherently safer designs require that hazards are recognized early and so construction of a bungalow rather than a house in a potential floodplain might not be such a good idea.

Many commentators have noted that bulk chemicals production is being transferred from the major, developed countries, such as countries in Europe, Japan and the USA, to lower cost locations for new plant. The major advantage is due to lower feedstock costs, although labour and capital cost reductions might be significant as well. Such ‘low-cost’ locations are often developing countries, such as China, India, Iran, Vietnam, Malaysia, etc., where the labour costs are certainly lower. This transfers the hazards from the developed

0bc3b80c76d020c296aee9e89bb4d73a.doc2 23/05/18 Export Inherent Safety NOT Risk countries, (where, historically, the plants would have been built and are now being decommissioned) to the developing countries.

These new plants are built and operated to the same high standards that the companies insist upon worldwide. However, the hazards are larger, because most of the designs have not changed and the plants tend to be larger than those that have been built before. The risks are greater initially because not only does the hazard increase with scale but so does the likelihood of realisation. The risk might increase over the years that the plant is operating for reasons described in the paper.

This conference is to mark the 20th Anniversary of the Bhopal Gas Tragedy: Experts from around the world will gather to summarise the significant progress made in process safety since 1984 and the current activities in various related areas. They will deliberate on directions for future course of action on which depends the very survival of the process industry.5

There have been many advances in process safety since Bhopal, not least those in inherent safety – Bhopal was the worst example of an inherently unsafe plant where the hazards have been realised to devastating effect. However, inherent safety remains a philosophy that is much admired but seldom practised to reduce major hazards. I contend that the key future course of action should be that the industry practise what it has endorsed for so long and make the new generation of plants being built in the developing world inherently safer. This is the only credible way to reduce the risks to acceptable levels. Otherwise, the industry might not survive future disasters on the scale of Bhopal.

THE CHANGING GEOGRAPHICAL DISTRIBUTION OF CHEMICALS PRODUCTION AND SCALE OF OPERATIONS

I compiled a list of new plant announcements as reported on the ‘Contracts’ page of the British Institution of Chemical Engineers house magazine, ‘The Chemical Engineer’, and in the pages of the UK magazine, ‘Process Engineering’.

In the one year period covered by magazine issues dated September 2003 to August 2004, a total of 19.6 million tonnes of new or expanded capacity was announced. In the following breakdown of this figure, the numbers are millions of tonnes. Of this 19.6 total, 15.9 and 3.7 was for organic and inorganic chemicals respectively. The majority of the organics were petrochemicals. The country with by far the largest announced new capacity was Saudi Arabia with 10.6. Saudi Arabia satisfies the ‘low-cost’ criterion because of its low feedstock cost but should Saudi Arabia be classed as a developing country? I would suggest that it is different from other developing countries for the purposes of my arguments in that its chemical plants are almost exclusively designed and operated by expatriates and it has well- developed centres of chemicals production that are operated to ‘Western’ standards.

There was one capacity expansion announced for the UK (0.4 chlor-alkali) and the rest (8.6) was all in developing countries. Iran had the most with 3.93, followed by Egypt (2.08) and China (1.87). The other countries appearing in my list were: Thailand (0.64), Malaysia (0.06), Brazil (0.01) and Vietnam (0.01). The new plants were all set to produce bulk chemicals with the possible exception of one in Vietnam with a capacity of 6500 tonnes per year of isomerates.

News stories that accompany the announcements of new plants and capacity expansions often claim that they are world-scale or that the location now has the largest production of the chemical in the world, etc. The size of the plants and complexes seems to be increasing.

A recent paper6, presented at the 2001 Asia Pacific Safety Symposium and written by two senior figures in large petrochemicals producers, claims that the capacities of all process plants have trended upwards over the preceding decades but that the designs have not changed. They provide some evidence of this for ethylene crackers and go on to argue that this large localised supply exerts upwards pressure on the capacity of local olefins consuming plants, for example ethylene oxide and polyethylene.

Thus, a cursory survey of contracts data and literature survey confirms that production of bulk chemicals is being transferred away from the developed countries to less developed ones and that plant capacities are increasing. Clearly, we need detailed research to confirm and define the extent and destinations of the transfer and the rate of capacity increase.

Let us now examine the risk implications of these effects.

RISK TRANSFER

Given that the capacities of the new plants are increasing and that they mostly use existing designs, the size of the hazards is increased either in proportion to the necessary inventory increases or over and above this. For example, piping inventories increase more than linearly with capacity6. If equipment, for example columns, heat exchangers and flare systems, has to be duplicated or tripled, etc the inventory and therefore the hazard will rise more than in proportion to the capacity increase. However, the risks are increased even more.

Windhorst and Koen6 make the case that, while the designs of new plants are simple linear extrapolations of existing designs of much smaller plant, the risks increase exponentially. To justify this assertion they made quantified risk assessments of ethylene plants. They concluded that the individual risk of the most exposed person, increases to the power 1.33 of capacity and that risk is proportional to the square of capital.

They state a number of reasons for this effect. Some of these are:  larger equipment and nozzle sizes result in larger release rates and amount released and also increased probability of ignition;  bigger maximum rate of energy release;  increased adiabaticity (larger equipment has lower heat loss per unit of inventory) causing higher temperatures during an upset and hence different runaway reaction behaviour or unexpected combustion reactions;  management of change is more complex because of the greater number of support systems;  larger reactor volumes, whereas reactor control enhancements may not be commensurate and special safety systems may be required;  duplicated, triplicated, etc equipment requires much more complicated piping, many more valves, flanges, welds, etc – all of these increase the probability of a release.

In addition to the increased risk posed by the larger capacity plant. Other factors compound the increased risk for plant built in developing countries. Many of these are to do with people, their culture and history.

In most of the developed countries the chemical industry has developed over many years, for example chemicals production in the UK and Germany started centuries ago. This has resulted in a comprehensive body of appropriate legislation and regulations that have proved their worth over the years. Just as importantly, a culture has grown up of respect for the inherent hazards of chemicals manufacture and a determination to do it safely, not just within the industry but in society. These factors have resulted in the industry having an enviable safety record. For example, the worker fatal accident rate of the UK chemical industry is better than most other sectors and I cannot discover when the last person was killed offsite by a chemical accident in the UK. There have been none this or last century. This excludes explosives, such as nitro-glycerine and dynamite, which have killed significant numbers of people during the two world wars by massive explosions in stores and plants.

However, this might not be the case for plants built in developing countries where the regulations might not exist or be inappropriate or there are insufficient resources for enforcement. For example, it is inconceivable that people would have been allowed to live as close to a major hazard site in the UK as they were at Bhopal. There might not be any emergency response planning for people living near the plant and these people might not be told about the hazards (both as at Bhopal).

These deficiencies might not be a problem when the plant is new, is making money and is run by well-trained local people and expatriates – chemical companies insist upon the same good standards world-wide. However, it is when the plant is ageing and is losing money (as the Bhopal plant was) that problems are likely to occur due to reduced staffing and skipped maintenance, for example. The chances of safety suffering on a very large plant (as Bhopal was) are greater when demand for the product drops, because the loss due to closure would be higher and the breakeven production is large.

Companies might underestimate the difficulties of operating in countries with different cultures and traditions. For example, in some new locations for chemical plant loss of face is a hugely important issue. I have heard of serious safety incidents caused by local personnel saying there was no problem – when there was.

Problems might be more likely if ownership is subsequently transferred to local companies or to the state. Then the local operators might lose the experience of the expatriate experts and they will not have the cultural knowledge of chemicals production that exists in the developed countries.

Finally, major hazard chemical installations are clearly ‘soft’ targets for terrorists, wherever they are located. Less developed countries may not have effective security to counter this threat. It is self-evident that if there are no or only small hazardous inventories in a plant then it would not be a terrorist target. Avoiding or minimising hazardous inventories is the most important strategy of inherently safer design. Therefore, building inherently safer plant is a ‘no-brainer’ for countering terrorism targeted at chemical plant.

Leaving aside terrorism, inherently safer plant should be the norm for lesser developed countries. Because then adequate risk reduction is not dependent upon regulation, or well-

0bc3b80c76d020c296aee9e89bb4d73a.doc5 23/05/18 Export Inherent Safety NOT Risk trained operators or protective systems, etc. The risk is low because the hazards are small. However, inherently safer plant are not the norm. I now examine why this is so and make some suggestions for overcoming identified barriers to inherently safer production.

THE BARRIERS TO INHERENTLY SAFER PLANT AND HOW TO OVERCOME THEM

Firstly, how do we know that the new plants are not built to inherently safer designs? Because none of the project announcements mention inherent safety and people in the industry tell me that existing technology is used - any ‘innovation’ there is building bigger plants to achieve greater economies of scale. If the new plants were inherently safer, the press releases would surely mention it.

Perversely, it seems that the inherent aversion to commercial risk and the conservatism of the chemical industry has prevented the widespread adoption of the best available technique for reducing risk to people and the environment – the inherently safety philosophy and its practical application in inherently safer design! This aversion and conservatism finds expression most often in the approach to process development (with its overriding focus on time-to-market), cost estimation, evaluation of projects and business risk. Competitive pressures and emphasis on speed to market make inherently safer designs too (commercially) risky!

My recent paper at Hazards XVIII7 provides a comprehensive view of the barriers to inherently safer plant, which may be summarised:  inadequate project evaluation, because of lack of appropriate and tested inherent safety assessment tools and limited resources that do not allow ‘space’ for inherent safety;  inflexible capital and operating cost estimation and economic feasibility assessment methods that do not credit inherently safer designs with their due cost advantages;  no enforced legislative requirements for inherently safer plant;  no incentives for implementing inherently safer designs.

Why should the companies risk new technology, when the existing technology is safe enough? The flaw in this logic is that the existing technology is believed to be safe enough in a developed country (because there are very few major loss of life incidents) but my contention is that it will not even be safe enough used in a larger plant in a developing country. Therefore we must strive to ensure that the new plants are designed and built according to the principles of inherent safety.

Encouraging Inherently Safer Production

Let us examine each of these barriers in turn.

Project evaluation One of the reasons for not implementing inherently safer designs most mentioned by respondents to a recent survey is the lack of tools for making the required analyses8. In fact, there are a number of published tools for inherently safer design, some of which, for example

INSET9, have had considerable resources expended on development with a consortium of companies. However, most of the new plants are for producing established bulk chemicals. Alternative designs are well known and conventional tools such as the Dow Indices and quantified risk assessment (QRA) will already have been used to assess the relative hazards and risks. The inherently unsafe areas of existing designs are also well known. So, the problem is not producing new inherently safer designs but having the will to spend a little more time developing existing inherently safer designs and then to take the commercial risk of implementing them. Shinnar12 comments that whereas the first fluid catalytic cracker went from initial design to full production in only 18 months in 1938, it might take 18 months today to pass a management decision to build a pilot plant. The need for more decision- making time by management can have negative implications for engineering, particularly for inherently safer engineering.

Moreover, there should be a return on this commercial risk, because intuitively inherently safer designs offer cost savings and profit enhancement:  inventory reduction will generally reduce costs because smaller vessels cost less;  simpler plant costs less because there is less equipment and ancillaries;  avoiding hazards also avoids the costly hazard control measures.

These arguments apply equally to capital and operating cost, because reducing count, size and complexity of equipment, reduces utilities, labour, testing and maintenance costs. As Henry Ford succinctly put it: “what you don’t fit costs you nothing and needs no maintenance”.

Industry insiders claim that equipment related to safety, health and environmental protection represents 10-50% of the capital cost of conventional plant and that the potential savings are not appreciated because this equipment is seen as standard items that will inevitably be required. On operating cost, achievable cost reductions for inherently safer plant are 10% for maintenance and 20% for downtime. Payback times are typically less than 2 years for projects involving inherent safety.

Such economic benefits are not apparent at the point that the major project decisions are made. This is because early economic estimates do not allow for the decreased capital and operating costs of inherently safer plants. Therefore, in the absence of a compelling argument for doing otherwise, the conventional design will normally be chosen.

Inherent safety legislation Inherent safety is not yet compulsory in most safety legislation but it is mentioned or described in existing regulations and guidance, for example in the UK, where an inherently safer approach is recommended. There is a trend towards regulation that focuses on reducing the size of hazards and the possible consequences, particularly to offsite populations, rather than reducing the statistical risk of harm. This trend favours the adoption of inherent safety and it is likely that it will appear in future legislation. Therefore, companies ought to adopt an inherently safer approach to ease current and future regulatory compliance.

Experience of Inherent safety Legislation In the USA legislation enacted locally in Contra Costa County, California (CCC) insists upon inherently safer systems (ISS) unless evidence is presented that the financial impacts would be sufficiently severe to render the inherently safer system as impractical10.

This legislation was prompted by a series of major incidents in CCC, which is near San Francisco, mostly involving refineries. This legislation has caused considerable problems for the ‘major hazard’ sites in CCC and that the County has issued a guidance document. It remains to be seen how this legislation will impact actual process design in this locale. Early reports indicate that hazardous inventories have been reduced, chlorine is now being generated in-situ for water treatment or else alternatives, such as ozone or ultra violet light, are used instead and aqueous ammonia is used instead of anhydrous. Major hazard sites are introducing procedures for implementing the ISS requirements of the ordinance.

Forthcoming Legislation? The Federal USA (therefore with much wider applicability) Chemical Security Act of 2003 was first introduced in 2001 in response to ‘911’. It was withdrawn but has recently reappeared. It is sponsored by Senator Jon Corzine and co-sponsored by Hillary Clinton, amongst others. Some of this bill reads like excerpts from a Trevor Kletz book on inherently safer design and is very prescriptive. In response to this Democrat bill, Republican Senator Inhofe has introduced the Chemical Facilities Security Act. This bill deals with plant security only but it is rumoured that some Republicans want amendments to include inherent safety.

Inherent safety is on the regulatory agenda in the USA. It is perhaps ironic that, at this time, companies that might have to comply with the proposed legislation ‘at home’ are building plants that would not so comply in overseas jurisdictions.

It behoves Governments in developing countries to enact legislation insisting where possible on inherently safer plant. After all, if the developed nations are moving in this direction and their companies insist on the same standards world-wide, then they ought to build inherently safer plant world-wide.

Incentives for Inherent Safety The incentive for inherently safer plant is as simple as the concept:

Inherently safer plants are Safer

However, this has not resulted in installations so far. Cynics might say that rather than build inherently safer plant the risk has been exported to be borne by people who do not matter so much. I am sure that this is not the case, but in order that more cynical people or those with other agendas do not come to this conclusion and promulgate it against the plant owners, would it not be in everyone’s interests to build inherently safer plant? Adoption of inherent safety can help to improve the reputation of companies. It seems obvious that it is better to operate inherently safer plants than to control large hazards. The public, even in developing countries, understand that low probability events can happen – people do win lotteries. The absence of hazards is far easier to communicate than acceptability of risk.

SUMMARY AND THE WAY FORWARD

The Bhopal plant was a large, inherently unsafe chemical production facility in a developing country that was majority owned and operated by a company from a developed country. An accident on the plant caused the world’s worst industrial disaster, wherein 3800 people died, according to the State Government of Madhya Pradesh1.

This accident ought to be remembered for all time as a terrible warning of what can happen when hazard control and mitigation fails. Instead, we seem to be forgetting the lessons learned. Because a new generation of potential ‘Bhopals’ are now being built in the developing world, largely by companies from the developed nations.

This paper presents a personal view that the current transfer of production of bulk chemicals from developed to developing nations poses unacceptable risks to the people and the environment in these new locations. This is because the risks increase more than linearly with the on-going capacity increases of the plants and the developing country locales are less able to cope with the increased hazards.

Of course this is just my opinion, based upon limited data and research. Therefore, I appeal for research into the changing geographic distribution and scale of chemical production and for analysis of the new risk profile due to any identified changes.

The Bhopal plant was inherently unsafe. It could have been inherently safer, which would have spared all those lives that were lost. This simple fact ought to spur Governments and regulators with jurisdiction over the locations of new facilities to insist upon inherently safer designs. The paper makes the case for building inherently safer plant to reduce the hazards and risks borne in the plant locations. Even if these safety benefits were not enough, the economic, security and ‘PR’ advantages of inherently safer production should convince those people taking investment and fundamental design decisions to sanction inherently safer designs for new facilities. However, instead, bigger and bigger plant is built to conventional, ‘tried and trusted’ designs but which have larger hazards and pose even larger risks because of the increased scale and unusual location.

This trend also poses an unacceptable risk to our industry. The chemical industry ‘survived’ the appalling loss of life at Bhopal but the Union Carbide Corporation did not. The industry urgently needs to make inherently safer plants a reality, rather than a much-lauded ideal. This strategy might seem commercially risky but in the long term it is the only way to ensure the sustainability of the industry, wherever it is located. Would the industry survive another ‘Bhopal’?

I have recently been privileged to attend meetings of two bodies that were both set up in response to disasters where the scale was due to inherently unsafe plant. The International Process Safety Group was set up after the Flixborough disaster that prompted Trevor Kletz to establish the principles of inherent safety11. It is a strange coincidence that 2004 is also the 30th anniversary of Flixborough, where the realised hazard was the of the other primary category: fire and explosion. The other group is the Centre for Chemical Process Safety, which was set up by the AIChE in response to the Bhopal disaster.

At both of these meetings I was very impressed by the open and honest discussion of incidents and future policy amongst representatives of companies, for the benefit of the industry. However, both these meetings were attended only by safety professionals.

My dream is for a similar forum for process industry chief executives and decision makers, where they could be informed of and discuss risk issues and formulate an industry response. For example, would Warren Anderson, Chief Executive of Union Carbide, have allowed the Bhopal plant to continue operating as inherently unsafely, had he known about the size of the hazard and that all the risk to his company was concentrated in that one loss- making plant in India? I believe that such a forum of chief executives would decide to:

Export Inherent Safety NOT Risk

I encourage everyone to try to make it happen.

ACKNOWLEDGEMENTS

The author gratefully acknowledges the helpful comments made by Trevor Kletz and Jan Windhorst during the writing of this paper.

REFERENCES

1. Union Carbide Corporation, 2001-2002, http://www.bhopal.com/. 2. Gupta, J.P., 2003, Bhopal: …Eighteen, going on Nineteen and Fading?, Process Safety and Environmental Protection, 81, July, 227-228. 3. Kletz, T.A., 1998, Process Plants: A Handbook for Inherently Safer Design, (Taylor & Francis, Bristol, PA.) 4. Jones, D.A. (ed.), 1992, Nomenclature for Hazard and Risk Assessment in the Process Industries, 2nd edn (IChemE, UK) 5. Bhopal and its Effects on Process Safety conference website, http://www.iitk.ac.in/infocell/announce/bhopal/ 6. Windhorst, J.C.A. and Koen, J.A. (2001), Economies of scale of world-scale plants and process safety, Proceedings of Asia Pacific Safety, Kyoto, Japan. 7. Edwards, D.W., 2004, Are we too risk-averse for inherent safety? An examination of current status and barriers to adoption, Hazards XVIII, (UMIST, Manchester, UK, Nov. 23-25) 8. Gupta, J.P. and D.W. Edwards, 2002, Inherently Safer Design - Present and Future, Process Safety and Environmental Protection, 80, 115-125. 9. INSIDE Project, 1997, Inherent SHE: The Cost Effective Route to Improved Safety, Health and Environmental Performance, (London, June 16-17, 1997, IBC UK Conferences Limited, London). 10. http://www.co.contra-costa.ca.us/ 11. Kletz, T.A., 1976, Preventing Catastrophic Accidents, Chemical Engineering (US), 83, 8: 124-128. 12. Shinnar, 2004, A Systematic Methodology for the Design Development and Scale-up of Complex Chemical Processes. The Role of Control and Concurrent Design., Industrial and Engineering Chemistry Research, 43, 2, pp. 246-269.

Bhopal plant – the chemistry Raw material  Intermediate  Product

CH3NH2 + COCl2  CH3OCN + 2HCl Methylamine + phosgene  MIC + HCl R1 R2 I STEP 1 40 te OH OCONHCH 3  CH3OCN + MIC + -naphthol  carbaryl I R3 P STEP 2 7

Alternative carbaryl chemistry

Raw material  Intermediate  Product

OH OCOCl COCl + 2  + HCl -naphthol + phosgene  chloroformate + HCl R3 R2 I STEP 1

OCOCl OCONHCH

+ CH NH 3 3 2  + HCl chloroformate + methylamine  carbaryl + HCl I R1 P STEP 2 9

Figure 1, The Bhopal plant chemistry and an alternative route to the product, carbaryl, that does not make methyl isocyanate (MIC).

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