Staying within the rules

Published:  10 November, 2015

Updates to the COMAH regulations mean that companies must work harder if they are to remain in compliance, says Jeremy Gadd, head of instrumentation, control & automation at GSE Systems, Inc.

There’s a general understanding that regulations, once introduced, are immutable: they are fixed, and you must simply follow them to the letter in order to be in compliance. However, this is far from the truth. Instead, amendments and updates mean that regulations that were once well understood are now outdated: complying with them becomes a moving target.

The Control of Major Accident Hazards (COMAH) regulations are a case in point. The rules – which are intended to prevent major accidents involving dangerous substances – apply mainly to the chemicals industry, but affect other sectors that store dangerous substances. They are in place to prevent and mitigate the effects of major accidents on people and the environment.

COMAH regulations were updated this year and while many of the rules are familiar from the earlier 1999 regulations, there are a few major changes, including: the list of substances covered; the need for cooperation from designated authorities when testing an external emergency plan; and stronger requirements for public information.

Keeping up with the earlier version of COMAH was challenging enough. Now, with the amendments, staying on top of the rules – and remaining in compliance – is harder than ever, but it can be done by maintaining a proactive approach.

Key responsibilities

Health, safety, and environmental (HS&E), operational and engineering managers are responsible for COMAH compliance, and for submitting COMAH safety reports. These reports require evidence that internal systems are compliant with the regulations, and are managed, tested and maintained correctly. If a company cannot demonstrate compliance, the Competent Authority (CA) is likely to increase monitoring and intervene more frequently – increasing the time and cost that must be spent to demonstrate that management systems are robust. The Health & Safety Executive (HSE) is the prevalent CA, but others include the Environment Agency and its regional equivalents. In the event that one of these authorities finds failure to demonstrate compliance, their case of action can be an improvement notice, a prohibition notice, or prosecution.

Electrical, Control and Instrumentation (EC&I) systems are a vital part of any plant – and are covered specifically within the COMAH regulations. An operational delivery guide* describes the approach that the CA follows for inspecting EC&I systems at COMAH establishments, specifying the benchmark standards used to assess risk management by the operator. Though aimed at inspectors, it can help companies in their self-assessment regimes.

EC&I equipment and systems provide important prevention and mitigation measures against major accidents. Examples include: instrumented process safety measures such as trips, alarms and interlocks; protection against electrical sources of ignition; protection against large releases of electrical energy; and, reliability and availability of utilities.

According to HSE: “Our research shows that failure to adequately control process conditions, especially during normal operations, is responsible for the loss of containment of hazardous substances.”

Documented proof

When inspectors talk about evidence, this usually refers to documentation. It includes initial design documentation, studies and specifications. The CA will also assess how EC&I equipment is maintained and tested – and how this is recorded – as well as employees themselves. For example, how is the calibre of design and maintenance staff assessed? And, are they suitably qualified and trained in these tasks?

The CA inspection results in a ‘performance rating’ for each EC&I topic. In this case a low figure is desirable, and is a measure of how closely a company adheres to the benchmark standards and relevant good practice: so, a score of 10 is ‘exemplary’, while 20 is ‘fully compliant/good’. At the other end, 50 is ‘very poor’ while 60 is ‘unacceptable’.

As well as this objective scoring approach, inspectors use their own judgment to decide how deeply to test operator performance and the potential underlying causes of failure before they make a regulatory decision.

Priority areas

Three priority areas within EC&I are covered by the benchmark standards: explosive atmospheres (or hazardous areas); functional safety; and electrical power systems.

In each of these three areas, companies are assessed according to five main criteria: hazard and risk assessment; engineering and design; and operation and maintenance. All are underpinned by competence (of staff) and an effective safety management system.

For hazardous areas, the relevant regulations and standards documents are DSEAR Regulations 2002, DSEAR ACOP L138, and BS EN 60079. These documents relate to: risk assessment; selection, design, installation, maintenance, and periodic inspection of equipment; and, the management of these systems. The Functional Safety standards and guidance documents are BS EN 61511 and EEMUA Publication No. 191. These documents relate to: Safety Instrumented Systems (SIS); Basic Process Control Systems (BPCS); and Alarm Systems. Electrical Systems are covered by Regulation 4 of the Electricity at Work Regulations 1989 (EAWR), which covers the general safety of electrical systems and includes specific references to construction, maintenance, and operation.

In explosive atmospheres, inspectors look at the management, design, installation, operation and maintenance of systems that cut the risk of electrical sources of ignition – arising from electrical and instrumentation equipment, lightning, static electricity, radio frequency radiation and cathodic protection. They also consider the mitigation of releases using flammable and toxic gas detection, and fire detection.

In engineering and design, for example, the CA will look at whether enough effort has been put into this stage. Much of it may seem obvious, but inspectors are looking for hard evidence. In gas detection, for example, the types of sensor that considers cross-sensitivity of different gases is required – as is the positioning of detectors and that indication of gas concentration and where they alarm to. In operation and maintenance, does portable equipment – used to carry out testing in hazardous areas – have the same inspection criteria as fixed equipment?

Inspections for functional safety are concerned with systems such as process control, safety and alarm systems – which cut the risk of major accident.

Within engineering and design, the safety system should be properly defined by a Safety Requirements Specification (SRS) document, which outlines its basic requirements, defining parameters such as acceptable spurious trip rates, operational constraints, whether the process is continuous, if there are shut-down periods, and if there are redundant process streams.

If a facility does not have an SRS – and this is relatively common – it is not too late to develop one: it adds value in terms of benchmarking the performance of the existing system, and is a good basis for developing and adding to safety systems over the life of the facility.

Alarm systems need to be adequately designed and suitably structured in the way they are presented to operating teams, in order to avoid extensive or inappropriate responses to alarms. In the Texaco Milford Haven refinery explosion in 1994, for example, there were too many alarms: in the 11 minutes before the explosion, two operators had to recognise, interpret and act on 275 alarms.

For electrical systems, inspections are concerned with: the initiation of major accidents by electrical equipment through fire and explosion; and ensuring these systems provide the reliability and availability to prevent or mitigate accidents and prevent danger to personnel.

In hazard and risk assessment, operators should understand the impact of catastrophic failure of electrical equipment, as well as the effect of electrical failure on utility systems – including cooling water systems, fire alarms, evacuation systems and many more.

Within engineering and design, inspectors test for effort in verification of earthing systems. They look at wiring regulations, equipment selection, and what safety measures are in place to prevent inadvertent contact, lightning strikes, arc faults and fire.

For competency management – in all areas – companies should consider an ongoing training regime to assess and verify current confidence levels of both internal staff and that of contractors and vendors. Companies also need to understand exactly who is the competent person – or people – within their organisation.

This is not an exhaustive guide to COMAH, but should go some way to showing which documentation – and what type of regime – is needed in order to remain in compliance. The best advice however is to refer to specialists in EC&I compliance for COMAH such as GSE Systems, which can take site based assessments, offer training to personnel and deliver designed solutions to achieve and maintain compliance.

* The COMAH operations delivery guide for inspecting EC&I systems can be downloaded from

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