Curtin University of Technology

Department of Civil Engineering
Environmental Engineering Management 690

Assignment 2

Management of Health and Safety at Work in the Chemical Industry
Prepared for: Professor Geoff Taylor By: Mohammed Alshiha Student ID: 13884145 Date: Jan 1st 2010

1.0 Introduction

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Declaration

(i)

I have read and understood Curtin University’s policy on

plagiarism and I confirm that the work submitted on the 1st of January by me is my own work, and that the work of any other person contained therein is clearly acknowledged.
(ii) The work has been written since the 8th of December 2009.

(iii) The references in the work do directly relate to the material appearing immediately before them in the text.

(iv)

All word-for-word quotes from another author are in quotation marks.

Mohammed Alshiha ID#13884145

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Contents
1.0 Introduction ................................................................................................................................ 3 2.0 Safety Management System ........................................................................................................ 5 3.0 Risk Analysis ................................................................................................................................ 7 3.1 Search for hazards ................................................................................................................... 7 3.1.1 Systematic search for hazards ........................................................................................... 7 3.1.2 Types of hazards in the chemical industry ......................................................................... 8 3.2 Risk assessment ....................................................................................................................... 9 3.3 Risk reduction measures ........................................................................................................ 10 3.3.1 Hazard control hierarchy ................................................................................................. 11 4.0 Safety in the Chemical workplace .............................................................................................. 13 4.1 Inherent Safety ...................................................................................................................... 13 4.2 Hazardous Materials .............................................................................................................. 15 5.0 Conclusion ................................................................................................................................. 16 References ...................................................................................................................................... 17

“A perfectly safe airliner will never leave the ground” Bahr 1997, p5.

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1.0 Introduction
A face mask made from animal bladder was devised by a roman scholar called Pliny the Elder in the first century AD, after he perceived the health risks faced by those working with zinc and sulphur. The concept of occupational and health safety was present even before the time of Pliny. The lead toxicity in mining was noted by Hippocrates in the fourth century BC. More recently, Agricola, a German scholar wrote a book in 1556 describing diseases of miners as well as prescribing preventative measures. The idea of anticipating and

evaluating conditions in the workplace that may cause harm to workers is the underlying concept behind occupational health and safety (Brown, 2007). The use of chemicals in modern times is highly extensive. Chemical use by humans ranges from activities such as increasing agricultural productivity, prevention and control of diseases, processing of chemical products etc. It is estimated that one thousand new chemicals enter the market annually and approximately 100,000 chemicals are actively utilized globally. The extensive use of chemicals implies that there are a lot of chemical and industrial activities aimed at producing such chemicals (Cholarisk, 2009). It is to be noted here that the heterogeneous and reactivity nature of chemicals makes them hazardous to both humans and the environment. As such, production of chemicals in industries requires a comprehensive detail of safety and risk management practices. Some of the common varieties of chemicals in production include inorganic and organic chemicals, pesticides, paints, specialty chemicals, dyestuffs etc. The risks associated with chemicals may stem from their inherent nature where some are out rightly flammable, corrosive, toxic or explosive. Some other chemicals are hazardous in terms of their reactions when exposed to certain materials such as oxygen, water or other chemical elements (Cholarisk, 2009). As such, safety management practice in a chemical industry ought to address the fundamental composition of the chemicals in production which would help in designing an effective management practice. The management of safety in a chemical plant can be effective if the individual areas that are considered as risky are analyzed. This report will highlight some areas that are considered as crucial when assessing risks within a chemical plant. The establishment of a safety management system is considered of paramount importance and is discussed in section two of this report. This topic is then followed by a brief look at risk analysis starting

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from risk assessment to the control choices available. Section four of this report presents the concept of inherent safety in the chemical industry.

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2.0 Safety Management System
Like any other industry, the chemical manufacturing had its share of accidents, both minor and major, possibly due to the increased demands for the chemical products and the rapid advances in manufacturing technology. The increase in demand alone presents a hazard by itself. One of the most serious accidents in the history of this industry is the explosion at the Nypro Ltd factory in England in 1974. This explosion caused the death of 28 workers and the injury of 38, while injuring about 53 people from outside the plant. The damages extended to 1821 houses and the overall cost of the accident was estimated at over $100 million (Theodore et al, 1989). Accidents may occur anytime and place where there is a presence of hazards. Safety in organizations can fall a victim to the fast pace of industrial development and increased competitions. Successful organisations need to adapt safety system that manages safety aspects relating to technology, hazardous materials and personnel (CCPS, 1989). A Safety Management System (SMS) is a process of identifying, understanding and controlling hazards at the workplace (CCPS, 1989). SMS is different from one organization to another, but can generally be seen as having four basic functions, these are (CCPS, 1989):  Planning: in this function the safety policy and the objectives are developed by management. Under this function, management is expected to develop strategies for the health and safety in the organization as well as set up the required resources to carry these strategies. This is a management function and is also required by the Australian standard AS4801 (CCH, 2004).  Organizing: This function is responsible for delivering the structure and provides the responsibilities and accountability of the provision of the desired deliverables of the SMS. It may deal with setting the roles of the managing team and providing goals for the front line managers. The documentation and document control process may be established in this function.  Implementing: This is the main part of the SMS; this function represents the application of the developed strategies. This function sets the wheels in motion, and the execution of the work efforts (CCPS, 1989). The main activity under this function is the risk management process as it is addressed in the AS4801, and may cover the following (CCH, 2004):  Hazard identification

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 Safety audits  Capability  Training  Emergency responses etc.  Controlling: This is the evaluation stage and is the function that keeps the system on track and closes the management cycle loop by providing feedback on the performance of the system and to ensure that safety controls are delivering the right results (CCPS, 1989). In order for this function to perform well, the goals in the planning stage have to be clearly set and measurement values have be established for the system assessment.

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3.0 Risk Analysis
Risk analysis is a systematic method aimed at identifying, evaluating and controlling hazards in the work place (Bahr, 1997). A properly executed process risk analysis can lead to a safer environment as well as economic benefits due to the increased reliability of the process. Due to its nature, the chemical industry is perceived to be a threat to humans, society and the environment, leading to an increased demand on the industry to provide product and process safety and to avoid disasters, hence the paramount need for proper risk analysis. Risk analysis involves searching for hazards, assessing risk and identifying mitigations and preventions of hazards (Stoessel, 2008). These three functions of risk analysis are explained in this section.

3.1 Search for hazards
Finding hazards is a vital step in the management of health and safety in the chemical workplace. It is only after the recognition of the hazard that control measures can be identified and implemented. In order to successfully search for a hazard, one must know what a hazard is. A hazard is a dangerous event or situation that may harm humans, environment and property. Risk on the other hand is defined as a measure of severity and is the product of the consequence and probability of the event (Theodore et al, 1989). 3.1.1 Systematic search for hazards One of the detailed and most comprehensive stages of the occupational health and safety management system is the hazard search and identification process (Workplace safety Australia, 2007). This section presents some of the ways used to systematically identify and recognize possible hazards in the chemical workplace. These are (Stoessel, 2008):  Check list method: This method is based on identifying known hazards, and depends on historical data and past experiences. The process description or the operating mode is the base for this method, deviations from the base mode are identified and analysis is performed if there exists a hazard from these deviations. This method works well in environments where more than one process is performed on a plant (Stoessell, 2008)  Failure mode and effect analysis: In this method, each component of the process is systematically analysed. The method involves identifying all possible faults that may

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occur in each element of the system. Once the failure modes are identified, the effect of these failures are analysed and evaluated (Stoessel, 2008). This method is most suitable for parts of the process that do not involve chemical reactions, such as , blending and crushing (Walker et al, 1993).  HAZOP: This process was particularly developed for the chemical industry and for the process industry in general, and is based on the failure mode analysis. It is the identification of hazards that can cause equipment failure. This mode may examine the process as whole or parts of the process. This process still needs the identification of failures and the evaluation of the consequences of these failures which is the same as the Failure and effect analysis method (Stoessel, 2008).  Fault Tree Analysis: this is a deductive method where the failure is given at the top of the tree and the analysis is to examine the causes of that failure. Each event that may cause the failure is treated as a failure and its causes are identified, and this process goes on for the next generation of causes. This process can be very detailed and too large to handle. In the chemical process, the analysis may stop at the identification of failure in elementary devices such as pumps and valves (Stoessel, 2008). 3.1.2 Types of hazards in the chemical industry Workplace hazards are divided into six general types, and these are (Workplace safety Australia, 2007):       Physical hazards Chemical hazards Biological hazards Radiation hazards Ergonomic hazards, and Psychological hazards.

This report is concerned with hazards in the chemical workplace; these hazards can be an addition to normal sources of hazard found in other industries. These specific hazards may include (Barton and Rogers, 1997):

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Chemical reaction hazards: These hazards can result from the release of heat due to exothermic reactions and/or due to out of control reaction.

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Operational hazards: This mainly represents the fire and explosion hazards. This hazard is relevant in the chemical industry, due to the nature of the material that may be stored or used at any time.

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Toxic hazards: A health hazard can easily arise when some chemical are inhaled or ingested.

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Environmental hazards: this is caused by the discharge of chemical material to the atmosphere, which can cause negative impact on the environment. The discharge may be intentional, accidental or due to emergency response (Barton and Rogers, 1997).

3.2 Risk assessment
To attempt the reduction of accidents and workplace disasters requires the understanding of the risks involved and their consequences. Risk is defined above as a measure of severity and is the product of the consequence and probability of the event. Risk assessment process follows the process of hazard identification and deals with the seriousness of the identified hazards. Risk assessment is defined as “is the process of determining the degree of risk associated with the identified hazard” (Donaldson, 1998, 15). There a number of elements associated with the degree of risk in this definition, these are (Workplace safety Australia, 2007):     The number of people affected The frequency of the hazard occurrence History of accidents resulting from the hazard The severity of the consequence of this hazard.

The result of the assessment could indicate if a control is needed and what type of control. Depending on the severity and probability of occurrence, a hazard can be considered minor if is unlikely to occur or its consequence is minor (Workplace safety Australia, 2007). As a result from the evaluation, hazards may be grouped in three different categories; these are (CCH, 2004):  Low risk

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 

Medium risk and High risk.

The process of risk assessment can be divided into the working on the three parts of the assessment, these are, the likelihood, severity, and priority of the hazards. At first the likelihood of the occurrence is determined and the results from this determination are qualitative and range from certain to highly unlikely. The likelihood determination is best done when assessing how the work is actually done rather than how it should be done in the workplace. Once the likelihood stage is over, the severity estimation begins. This process determines the severity of the consequence of the potential incident. Rating the severity requires all gathered information from hazard identification and assessment process, but most importantly, the assessors need to use common sense and be realistic when making their judgments (CCH, 2004). Any accident could result in death, for example a tripping accident from a cable on the floor could potentially result in death, but realistically the accident would result in bruising and may be fractures (CCH, 2004). The final step in the risk assessment process is risk prioritization. Here, the risk from the potential hazard is prioritized based on the determined likelihood and severity of the risk. This process takes into account the control measures currently implemented and then assign priority accordingly. The risks are ranked as trivial “low priority”, adequately controlled and not adequately controlled “high priority” (CCH, 2004, 107). Obviously, the high priority risk should be dealt with first. In the chemical industry; hazard evaluation is best performed by qualified personnel who possess knowledge in both hazard evaluation and the nature of the operations performed as well as the chemical characteristics and general chemistry of the processes. To avoid conflict of interest between production and safety, it is preferred that the assessor be part of an independent team (Barton and Rogers, 1997).

3.3 Risk reduction measures
Once the hazards have been identified and the risks associated with them are analysed, it is logical to look at ways of reducing and controlling these risks to produce a safer environment in the workplace. The major drive behind finding appropriate measures to control the hazard is the consequences of the lacking or inadequacy of hazard controls. The

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failure to provide adequate controls against exposure to asbestos dust, have resulted in the deaths of hundreds of Australians (Tillman, 2007). To control a risk, we need to look at either reducing the likelihood of the event or reducing the consequences “severity” of the hazard, because risk is the product of both of these (CCH, 2004, 49). Risk reduction methods can be classified into two perspectives, the action level and the action mode. The action level is divided into three strategies, hazard elimination, prevention or mitigation. The action mode on the other hand deals with the means to achieve the controls. This is divided into three different modes, technical, organizational or procedural means of control (Stoessel, 2008). 3.3.1 Hazard control hierarchy The hierarchy of hazard control was originally developed by NASA, and is useful and applicable in all industries (Bahr, 1997).The reason for calling it a hierarchy, is because of the order of choosing the control measure. For example elimination should be considered first, and if it is not possible, then consider the next measure. “The risk control measure selected must be the highest possible option in the hierarchy” (CCH, 2004, 49). This hierarchy of control is generally accepted across Australia as a process of risk control in the workplace (Work safety Australia, 2007). The hierarchal order of these controls is (Tillman, 2007):  Elimination: This control involves reducing risk by the complete removal of the hazardous substances, machines or processes from the workplace. This is the best way to deal with hazards because it means that the employees are working in an environment with one less hazard to worry about.  Substitution: Instead of eliminating, sometimes it is possible to replace the hazard with a less hazardous one. This means the substitution with something that has less severe impact or has a smaller chance of occurrence. This control does not eliminate the hazard, but it reduces its seriousness. For example replacing a highly toxic substance with a mildly toxic substance (Work safety Australia, 2007).  Engineering controls: The next control measure is the engineering out hazards. When the options of elimination and substitution are not possible, then isolating the hazard is a preferable option. Complete isolation of the hazard from the workers leads to complete neutralization of that hazard. This can be done with the use of

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machine guard and barriers as well as remote storage of the hazardous materials in the workplace (Tillman, 2007).  Administrative controls: This control aims at introducing safer working practices, when isolation and other engineering methods are not possible. These controls are normally documented work procedure such as standard operational procedures (SOP’s) and deal with hazards that cannot be eliminated and are necessary to work with such as working in high areas and hot works (Tillman, 2007).  Personal protective equipment (PPE): this option should only be considered when none of the above options can be implemented. This is the least preferred option because it means that employees are working in the presence of a hazard. PPE equipment can take the form of chemical suits, gloves, eye wear, hard hats, and respirators (Tillman, 2007). It is sometimes necessary to use a combination of the above methods to reduce the identified risk. Administrative control measures such as safety rules; training and standard operational procedures are usually used in combination with other control measures (CCH, 2004). Having identified the risks and worked out the proper control measures does not signify that the process is over. Once the control measures are identified, there is the need to perform further risk assessment to ensure that risks are at acceptable levels, and that all residual risks have been thoroughly examined. A residual risk is derived from the fact that complete elimination of risks is rare and that there always remain some risk after the implementation of controls. The residual risk consists of three components, these are, accepted risk, identified but misjudged risks and unidentified risks (Stoessel, 2008). Safety management system is an ongoing process and as such requires constant monitoring to evaluate its effectiveness. The consequences and likelihood of an event may change in time due to internal and/ or external factors and the effectiveness of the control chosen may be reduced. These changes give rise to the continual review of the controls and their effectiveness (CCH, 2004).

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4.0 Safety in the Chemical workplace
The 20th century witnessed a great deal of chemical plants disasters that should be used a guide when analysing the flaws in safety of chemical plants. A notable chemical plant disaster was in 1984 in Bhopal, India in a site owned by an American company subsidiary, Union Carbide India. During this accident, approximately 500 litres of water entered a tank containing a chemical gas, methyl isocyanate gas (MIC), initiating a chemical reaction that produced massive temperature and pressure build up. This caused the resulting chemical vapour composition to leak out under pressure to the surrounding human habitations. The gaseous leak affected people over a wide radius. Casualties have been estimated at more than 3,000 dead and an average of 500, 000 people injured and affected by the accident. Analysis into the disaster revealed that human negligence and poor design played a great role in the accident (Broughton, 2005). This section of the report discusses the concept of inherent safety and the presence of hazardous substances in the workplace.

4.1 Inherent Safety
Stallworthy and Kharbanda (1988) defines safety as a concept that covers risk assessment, hazard identification and accident prevention. In a chemical plant, measures of safety must be incorporated at all levels of design. Though the installations of safety measures are costly, their installation cannot be compromised considering the risk that lies there in. According to Taylor (1994) the best measure for safety is risk; a concept that is used in business to denote the possibility of loss. The fundamental concern in designing safe chemical plants should not only be to design ways that can enhance easy rectification of mishaps when they occur but should be to design an inherently safe plant that ‘designs out’ any potential hazards in the plant. This is to imply that a chemical plant should be designed in a way that to a large extent reduces the possibility of the occurrence of a hazard. According to Hendershot (1999), a chemical plant is described as inherently safe if it eliminates or reduces hazards associated with operations and materials used in the chemical processes. As such, elimination and reduction of potential hazards in a chemical plant should not only be a consideration in designing but should actually be an inseparable component during the initial design process. A fundamental acknowledgement is that hazards are dependent on their intrinsic nature or on the nature of their storage (Hendershot, 1999). There is a way that a hazard can be handled or stored that can considerably minimize its potential to cause

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harm. This therefore should be the primary concern when addressing the need for inherent safety. Since hazardous materials are dependent on their handling, there are several approaches that can be adopted to improve the aspect of inherent safety. These include: Reducing the quantity of hazardous material or distributing the hazardous material so as to minimize the risk of over concentration. In the Bhopal chemical disaster, it was the view of analysts that the damage incurred could have greatly been reduced if the lethal chemical, MIC would have been stored in relatively small containers. Techniques that can be used to improve inherent safety during design include the provision of protection layers between the hazardous agent and potential victims such as assets, people, environment etc. In the modern plants, the protection layer can encompass elaborate systems such as basic control alarms, automatic shutdown mechanism and physical protection devices such as pressure reduction devices (Hendershot, 1999). The design should also include mitigation aspects such as the construction of dikes surrounding the plant to contain chemical spill. In addition, the design should incorporate a community emergency response system that systematically communicates and notifies people in case of an emergency. If the protection layers are well organized and utilized, it would be possible to reduce the effects of a likely chemical mishap in a chemical plant (Hendershot, 1999). The achievement of an inherently safe chemical plant can be achieved during design through the following approaches: Proper zoning of hazardous areas-Hazardous areas on a typical chemical plant can be classified on two major aspects. One; on the probability of the presence of an explosive or flammable mixture, and secondly, on the chemical material present. Classification of a hazardous area can hence be classified either by specifying the area (area classification) or by specifying the hazardous material (material classification). In some cases, temperature level is used as a criterion for classifying an area as hazardous (HSE, 2009). In a safe chemical plant, hazardous areas are ‘zoned’, that is, they are identified and labeled appropriately based on the appropriate established standards such as the International Electro technical Commission, IEC) or the National Electrical Codes (NEC).

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4.2 Hazardous Materials
Hazardous materials have the potential to cause harm the health and safety of employees, when under the appropriate exposure or absorption conditions (Tillman, 2007). Some of the materials designated as hazardous includes: explosives, flammable gases / liquids / solids, oxidizing and radioactive materials, and some corrosive materials. Furthermore, an area that has widespread of hazardous materials is referred to as a ‘hazardous Area’ and as such requires the presence of strict control measures (HSE, 2009). As a safety control measure, hazardous areas should be clearly labeled while hazardous materials should be marked using well recognized tags within the plant. To prevent and limit employee exposure to harmful substances, it is common practice to create layers of safety between the hazardous areas and the workers on site.

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5.0 Conclusion
Occupational health and safety management starts at top management and flows all the way to the floor workers in any chemical plant. For any company to effectively reduce hazards and risk in the plant there needs to be a presence of a proper safety management system, which effectively evaluates and measures the risks and hazards present and concludes in the provision of an appropriate control measure. The system starts with top management setting the company policy on safety and their intentions to implement the program to achieve the objectives. Any safety system in any industry requires the investigation and identification of present hazards. Once they have been identified, the risk associated with these hazards are analyzed and prioritized, leading to the selection of the appropriate control system, that will reduce the severity or the probability of occurrences of the hazard. This report briefly brushed on the concept of inherent safety in the chemical plant design as well as hazardous area classification. Inherent safety is probably one of the best measures of hazard control, because it simplifies the process and engineers out the probability of risks.

www.hse.gov.uk/fireandexplosion/zoning.pdf#4. Stallworthy, E., & Kharbanda, O. (1988). Safety in chemical industries. GP courseware. Stoessel, F. (2008). Thermal Safety of Chemical Process. Weinheim: Wiley-VCH. Taylor, J. (1994). Risk analysis for process plants, pipelines and transport. London: E&FN Spon. Theodore, L., Reynolds, J., & Taylor, F. (1989). Accident and Emergency Management. New York: Wiley & Sons. Tillman, C. (2007). Principles of Occupational Health & safety. Crows Nest NSW: Allen & Unwin. Walker, D., Williams, T., Nawrocki, D., & Bridges, W. (1993). Managing Safety. Chemical Engineering , 3 (100), 90-100. Workplace safety Australia. (2007). National Handbook 2007. Sydney: Workplace Safety Australia.