• Operating limits move beyond design limits and known operating
• experience
• Inspection reveals accelerating or unpredictable deterioration
• Major repairs, refits or replacements are needed
• Decreasing intervals between inspections are specified as a result of
• diminishing confidence in continued fitness for service
• The costs of remedial work and inspection begin to outweigh the benefits
• of continued operation

Some of these issues could be relevant to relatively new plant, but equally there may be other cases where they may not arise for many decades of service, provided of course that there is an appropriate integrity management programme in place.

Why ageing equipment has become a regulatory priority

You may ask why the topic of ageing plant has recently become a regulatory
priority? There are a number of reasons, but perhaps the two most important are government and public expectations on regulatory authorities, and feedback from inspections.

The funding of Non-Departmental Public Bodies such as the Health and Safety Executive is linked to Public Service Agreements (PSAs). These set challenging targets for reductions in accidents and ill-health arising from work activities that HSE must meet in order to continue to receive government funding. In the Major Hazard Directorates of HSE, in order to secure the necessary reduction in accidents HSE has agreed to focus attention on key strategic themes related to the prevention of major accidents. One of the five major hazard themes concerns ageing plant (the others being loss of containment, human performance/human error issues affecting containment, emergency response, and safety culture and management of health and safety), and hence this is now an area for particular attention.

The other main reason for the steady rise in importance of this topic to HSE is simply a reflection of the state of the industrial infrastructure in the UK as we see it from our inspection work. Engineers, managers and operators will have their own views on the trend towards ‘lighter, faster, stronger, cheaper’ and the associated need to secure longer operating periods to maximise return on investment or reduce the number of workers employed to achieve a given level of output. All of these issues impact on the topic of ageing plant and our ability to manage plant safely.

For example, it is not uncommon to find pressure vessels and storage tanks still in operation after 60 years. These may be perfectly adequate for their required duty but it is often very difficult for owners and operators to provide a convincing demonstration that they have a comprehensive knowledge of the plant, a full understanding of all the active degradation mechanisms and a high degree of confidence in the continued fitness for service of the plant. We are also finding increasing numbers of cases where plant is being kept in service way beyond its original design life without technical justification that it is safe to do so.

Legislation relating to equipment containing hazardous fluids/pressure

A complete list of all the legislation relating to equipment containing hazardous fluids under pressure or at atmospheric pressure would probably run to several pages, but within the context of this seminar I will mention a few that are particularly important from a health and safety perspective.

Many of you will be familiar with the in-service inspection requirements placed on pressure systems such as steam boilers and air receivers that fall within the scope of the Pressure Systems Safety Regulations 2000 (as amended) [PSSR]. These regulations formalise the integrity management process for particular items of pressurised plant, and place duties on users and competent persons to ensure that the plant is fit for continued service, or withdrawn from service as appropriate. They are concerned almost exclusively with protecting the operators of the plant against uncontrolled energy releases, and in general take no account of the hazardous nature of the fluids contained.

For those items of plant storing fluids that fall outside the scope of the PSSR, the Provision and Use of Work Equipment Regulations 1998 (as amended) [PUWER] are relevant to managing containment integrity. In particular regs 5 and 6 require employers to make provision for adequate maintenance and inspection to ensure that the plant remains fit for continued service.

The most stringent requirements to manage containment integrity for non-nuclear on-shore plant are specified in the Control of Major Accident Hazards Regulations 1999 (as amended) [COMAH]. These regulations require operators of installations producing, handling or storing dangerous substances in sufficiently large quantities to take all measures necessary to prevent major accidents and limit their consequences to persons and the environment. Managing the integrity of installations that fall within the scope of the COMAH regulations requires a comprehensive knowledge of the plant, a full understanding of the degradation mechanisms and the ability to demonstrate to the regulating authorities that all measures necessary have been taken to prevent loss of containment, whatever the age of the plant or at whatever pressure the substance is stored.

There are also separate regulations covering the management of integrity of pipelines under The Pipelines Safety Regulations 1996 as amended, offshore installations under The Offshore Installations (Prevention of Fire and Explosion and Emergency Response) Regulations 1995 as amended and nuclear installations under The Nuclear Installations Act 1965 as amended. The latter also includes provision for Periodic Safety Reviews of nuclear installations where operators are required to demonstrate the continued fitness for service of ageing nuclear plant.

Legal responsibilities of users/owners/managers

Whatever the size or nature of the plant, someone will have a legal responsibility to ensure that the plant continues to remain fit for service and that risks to health, safety and the environment are properly controlled. This duty may fall to different people or entities under different regulations and may even fall within the remit of different regulating authorities.

In general, the duties under COMAH fall to the operator whereas the duties
under PUWER fall to the employer. Both users (and owners of mobile
equipment) and competent persons have duties under PSSR.

It should also be noted that the Health and Safety at Work etc., Act 1974 places duties on a number of parties including designers, manufacturers, importers and suppliers (Section 6), employers to their employees (Section 2), employers and self-employed to persons other than their employees (Section 3) and employees (Section 7). People and organisations that provide technical support or an in-service
inspection function as part of the integrity management programme may also be subject to duties under Section 3.

Current regulatory issues in ageing management

I’ll highlight a few current regulatory issues in my presentation. However,
assuming that we spend maybe 40 years in employment it follows that plant and equipment in service for more than 40 years will span the working lives of many workers. This poses particular difficulties for keeping records and the transfer of plant specific knowledge. Furthermore, the UK could experience skill shortages in key industries as older and experienced workers retire and younger people seek alternative careers outside science and engineering.

Maintaining plant specific knowledge and staff competence will be particular challenges for all those involved in managing the integrity of ageing plant. This is one reason why I am grateful to the IMechE for inviting me to speak on this important subject and I hope that we can today all benefit from the opportunity to share information with experts in the field of integrity management.

Kevin Allars
Head of Chemical Industries Division
Deputy Director Hazardous Installations Directorate
Health and Safety Executive
Tel: (+44) 0151 951 3127
Email: kevin.allars@hse.gsi.gov.uk

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