Summary of Meeting Paper

The 1996 Annual Meeting of the Society for Risk Analysis-Europe

An Outline of Industrial Risk Assessment Methods. Dr. R. Clark, BP Exploration Operating Company

Introduction

In the UK, risk assessment in industry is now required by a number of codes of regulations made under the Health and Safety at Work Act 1974, notably those which implement European Directives 82/501/EEC (the 'Seveso' Directive), 89/391/EEC (the Framework Directive) and 92/91/EEC (the Boreholes Directive). There is an over-arching requirement to assess all risks under the UK Management of Health and Safety at Work Regulations 1992, while more specific requirements are contained in other regulations, such as:

• Control of Industrial Major Accident Hazards (SI 1984/1902)
• Offshore Installations (Safety Case) (SI 1992/2885)
• Health and Safety (Display Screen Equipment) (SI 1992/2792)
• Manual Handling Operations (SI 1992/2793)
• Personal Protective Equipment at Work (SI 1992/2966)
• Provision and Use of Work Equipment (SI 1992/2932)
• Prevention of Fire and Explosion and Emergency Response (SI 1995/743)
• Pipelines Safety (SI 1996/825)

Further offshore regulations which include risk assessment will come into force in the near future.

In the context of this paper, the following definitions apply:

Principles for Risk Assessment

Neither the European Directives or UK Regulations prescribe any particular process by which the employer should carry out risk assessment, but the following general principles have been endorsed by the UK Health and Safety Executive (1):

• The risks assessed should be those which are significant. Time need not be wasted in assessing trivial risks which offer no real potential for injury or loss.

• Employers are not expected to address risks which are beyond the range of current knowledge. However, it is important that best advice is always available to everybody and that there is a high level of safety awareness in the workplace. The efficient and effective communication of information on risks must therefore take a high priority.

Sources of Risk

In broad terms, industrial risks can be considered to t>e created by two main categories of hazard:

Hazards created in the design or construction phase of a project may lie dormant until exposed by a particular combination of operating conditions or by an unforeseen change in operational requirements.

Hazards can also arise from organisational factors, such as alteration of manning levels, change of personnel, change of reporting function, etc., where these are not adequately controlled.

Priorities for Management of Risk

To enable health and safety to be managed adequately, all significant hazards in the workplace must be identified. The associated risks must then be evaluated and appropriate controls implemented within the general framework of an integrated health and safety management system.

It is important to ensure that the various options for controlling risk have been evaluated. For example, the 'Framework' Directive sets out the following priorities for control:

1. Avoid the risk, by elimination or substitution of the hazard

2. Combat risks at source, rather than simply mitigate their severity

3. Adapt work to the individual

4. Take advantage of technological and technical progress

5. Develop a coherent policy and approach to risk prevention
   

6. Give priority to those measures which protect the whole workplace

7. Workers need to understand what they need to do

8. Ensure the existence of an active health and safety culture

Employers should therefore try to remove the cause of a hazard where practicable, rather than simply to treat the symptoms. Substitution of hazardous chemicals, replacement of machinery to reduce noise, eliminating the need for access to confined spaces, reduction of hazardous substance inventories etc. are examples of actions which can be taken to remove or reduce risks.

Conversely, the provision of training and personal protective equipment are examples of safety management controls which may have to be applied to hazards which cannot be eliminated.

In general, risks are expected to be reduced to be 'as low as reasonably practicable' (ALARP). This term is generally accepted in UK law as meaning that the cost of a particular control measure can be weighed against its effectiveness when determining whether it is appropriate or not. This does not imply a great amount of discretion on the part of the employer, for example, the effect on profitability of an operation has no bearing on whether a particular control measure is reasonably practicable.

Some formal risk assessment techniques allow the term 'ALARP' to be expressed quantitatively, for example in terms of cost per life saved.

Risk Assessment Process

A generalised model of the risk assessment process is shown in figure 1.

Figure 1. Generalised model of risk assessment process.

Company health and safety Management systems will usually include various formal and semi-formal procedures for carrying out risk assessment. These provide a range of tools available which can be used to address the categories of risk referred to above, according to need.

Some examples of these procedures are listed below, together with the type of record which is produced for each.

Task-related hazards

Task-related hazards include those which are typical of the general work activity and the physical working environment on or offshore.

Examples:

• work at a height with risk of falling
• potential impact of severe weather
• small hydrocarbon emissions or leaks
• toxic or flammable atmospheres in confined spaces
• movement across slippery surfaces
• manual lifting of heavy weights being hit by a failing object
• use of hazardous substances with risk of personal contact

These types of hazard can be identified by systematic surveys and inspections of the workplace or work activities, particularly where the work is routine or repetitive. Checklists are used to prompt the assessment process and provide a reminder of the less obvious hazards.

The resulting risk assessment information can be used to develop standard work instructions. This reduces the need for an individual risk assessment on each occasion the task is performed, although it is still important for the team leader or individual to ask the question 'has anything changed?' before following the instruction.

In workplaces such as offshore installations, where a high proportion of work is normally carried out under the control of a written permit, risk assessment procedures may either be used as a supplement to the normal permit to work procedures, or, for lower risk activities, the issue of a permit alone may be sufficient, since this is primarily a risk assessment process in itself. Once the task has been completed, the working instruction must be updated to reflect any changes which have been found necessary, and any other documentation, such as training material, must be amended.

For tasks which are unfamiliar, highly specialised or otherwise known to be particularly risky because normal operating or maintenance practices cannot be applied, an individual task risk assessment can be carried out. This should form part of the work planning process and will be used to prepare a formal working instruction.

Process-related hazards

Process-related hazards include those which are related to the design, construction, commissioning or modification of particular items of plant and equipment. The hazards may affect the workplace alone or, in the case of major chemical processing sites, for example, they could potentially affect the surrounding community and the general public.

These types of hazard are mainly controlled through adequate specification of initial design, quality control throughout construction and commissioning and effective management of normal operations. The methods of risk assessment used vary according to the nature of the activity:

Acceptability of Risk

In assessing the 'acceptability' of an identified risk, it is often possible to refer to existing criteria against which the risk can be compared. For example, relevant standards may already be set out in legislation, official guidance or company operating practices; these might include:

• COSHH hazardous substance exposure limits
• noise exposure limits
• ionising radiation exposure limits
• scaffolding loading standards
• mechanical tolerances on plant
• physical condition of lifting gear, etc.
• technical integrity standards
• engineering codes of practice

Although standards of this type would normally be regarded by the regulatory authorities as an acceptable minimum to be achieved, organisations may have a policy of seeking to improve on the minimum. Such policies may be cost-effective, as well as beneficial in terms of company external reputation.

Where there is no objective standard against which to assess a risk, personal judgement must be used to decide whether the available controls will achieve an adequate level of acceptability. Under these circumstances, the experience and background knowledge of those involved are essential factors in ensuring the effectiveness of the assessment.

It is important to remember that individual perception of risk can vary considerably. The impact of this on the assessment process is discussed below.

Involving the Work Force

The site work force is likely to possess a great deal of detailed information on risk. Technicians and operators will have an intimate knowledge of how tasks are carried out in practice; this knowledge will be a valuable resource, particularly in relation to workplace inspections and task risk assessments.

In developing the use of the various risk assessment techniques listed above, steps should therefore be taken to encourage the involvement of the work force as much as possible and to draw out experience and knowledge which complements other risk information.

This process provides an effective means of reinforcing everyone's understanding of the nature of the site risks and of the role of individuals in ensuring that controls are applied effectively.

Recording of Assessments

The UK Management of Health and Safety at Work Regulations require the employer to record risk assessments. These records should contain a statement of hazards and risks and should be linked to other documents which describe the relevant controls in the safety and health management system.

There should also be an estimate of the number of persons who may be affected by each risk, particularly where there may be groups of employees especially at risk.

Each type of record should be retained normally for at least 2 years, either as hard copy or secure electronic data and should be auditable. Remedial actions arising from the assessments should be given a priority rating and tracked to completion, also in an auditable way.

There are cases, such as the assessment of personal exposure to chemicals, where it is necessary for the employer to keep records for at least 30 years or more. The format in which such records are kept will require careful consideration.

Risk Perception

As described above, the acceptability of certain types of risk can be stated in terms of objective performance standards or legal requirements, or the organisation may have developed and agreed internal codes or practices to provide guidance on specific risk assessment processes and performance standards.

However, there will be many situations where risk is difficult or impossible to quantify in these terms; the nature and therefore the acceptability of the risks will have to be judged subjectively, in the light of the experience and knowledge of those involved in the work.

It has been repeatedly shown (3, 4) that the subjective perception of risk level can vary considerably between individuals. Perception of risk can be affected by many influencing factors, such as familiarity with the task, work or personal stress, perceived benefit, time-scale of the risk, level of controllability, etc. Any of these factors could affect the judgement of an individual to the extent that he believes that a given risk will be under adequate control when an 'absolute', i.e. objective, assessment would demonstrate otherwise.

These factors could apply to any risk assessment, whether performed in a design office or at the worksite. The result of an erroneous risk perception, therefore, might be a significant design fault, a defective operating instruction, or a deterioration in the integrity of plant, creating the potential for an accident at some time in the future.

It is essential that the possibility that individuals can underestimate risk should be recognised. Line managers should always be aware that even the most experienced workers are occasionally capable of significant errors in assessing risks.

Some of the precautions which might be adopted by managers and supervisors to help reduce the possibility of errors of judgement include the following:

• be aware of biases or pressures which may affect risk perception by individuals
• for critical assessments, use a team approach to capture broad experience and avoid too much reliance on one person's judgement
• ensure that everyone's hazard awareness is kept up to date by encouraging networking of information and open discussion of good working practices
• ensure safety refresher training is up to date
• identify and discuss good and bad aspects of safety behaviour in the workplace at toolbox talks, safety meetings, etc.
• set a good personal example by consistent observation of safety standards
• encourage the understanding that all members of the team have a personal responsibility for the safety of themselves and other team members.

Practical Implementation of Risk Assessment

The following is a checklist of significant questions by which organisations might judge the effectiveness of their methods of risk assessment:

Application

• Is risk assessment an integrated and accepted management activity?
• Are adequate resources devoted to the assessment of risks?
• Is risk assessment used to prioritise risks and as an input to decision making?

Scope

• Are all activities regularly examined to determine hazard types and underlying causes?
• Do these examinations include hardware, technical systems, management systems and interaction of people within these categories?
• Is the Organisation aware of external pressures and threats?
• Is risk assessment undertaken for all new activities or modifications?
• Is risk assessment used to evaluate the implications of changes in staff, systems and external pressures?

Methods

• Are structured and systematic techniques used for identifying hazards and their causes?
• Are risks systematically assessed for probability and severity, using quantified methods where appropriate?
• Is an adequate range of risk assessment methods used, considering the nature of the activities?

Resources

• Is there adequate access to expertise in risk assessment methods?
• Are there competent individuals with relevant technical knowledge and experience available to advise?
• Do operational staff have adequate involvement in the risk assessment process?

References