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Charging for COMAH Activities - A guide

Sixth Edition - April 2010


Part 3: Illustrative examples of charges

3.1 This part contains examples of the level of activity the Competent Authority has so far devoted to examination of safety reports, planned inspection and investigation of incidents under COMAH. It also gives examples of activity seeking compliance with relevant statutory provisions (RSPs) on COMAH sites. This information is provided to help COMAH operators estimate the amount they may face for cost recovery. Operators are reminded that these examples may not be typical of their own business and that the effort expended by the CA will depend on the quality of the safety report submitted and the conditions which prevail at the establishment.

The amount of time and effort the CA devotes to enforcement of COMAH in any specific case may differ significantly from these examples.

3.2 The amounts shown include time spent on preparation and follow-up activities as well as direct site time. 

Examples of COMAH work at Top Tier sites

Example 3.1: Assessment & Investigation (Oil Refining & Associated Industry)

This oil refinery consists of complex refining process units, bulk storage and jetty facilities; employing approximately 350 employees. Hazards arising from the dangerous substances present include fire, explosion and toxic release with potential on-site and off site effects and environmental damage.


The safety report consists of a core volume and 9 installation reports. The time associated with assessment of these reports totalled:


Investigation regarding fracture of pipeline carrying COMAH notifiable substance leading to loss of containment. Involved discussion of relevant safety management systems such as plant modification procedures, design standards and safe systems of work.

Example 3.2: Assessment & Inspection (Chemical Production)

A medium sized petrochemical processing plant with material receipt, storage, distribution and utility facilities. Maximum number of 287 persons on site. There are flammable hazards associated with the dangerous substances with potential for significant on site off site effects and environmental damage. The safety report consisted of a core volume plus 6 installation volumes. Subsequent inspection specifically related to issues raised during assessment was made.



Example 3.3: Assessment & Inspection (Storage and Distribution)

An establishment comprising a number of large agrochemical warehouses. A range of agrochemical products are stored prior to distribution. Oxidising, flammable and toxic hazards are associated with products stored. The products have a potential to cause effects off-site in the event of a major accident, including environmental damage. Up to about 25 people may be on site at any one time. The safety report is in one volume.



Example 3.4: Inspection (Health & Hygiene)

A medium sized company employing approximately 150 people engaged in manufacturing pharmaceutical intermediates. Small to medium sized batches are produced to short time scales in multi-functional reactors. There are some exothermic reactions. A range of flammable, toxic and corrosive substances is stored. There is a potential for on and off-site major accident, including risk to the adjacent river. The site is top-tier by virtue of aggregation. The inspection has involved inspection of:

Example 3.5: Investigation & Enforcement (Oil Refining & Associated Industry)

Investigation of serious fire at a top-tier oil refinery. Extensive damage to plant but no injuries to personnel. Other key deficiencies identified, in addition to original cause of incident. Prosecution taken due to failure to ensure safety of employees.



Example 3.6: Investigation & Enforcement (Chemical Processing)

The investigation of serious fire at top-tier COMAH site which processes and stores highly flammable substances. Pipework failure resulted in release of hydrocarbon above the flashpoint which subsequently ignited. No injuries but significant localised plant damage. A COMAH Prohibition Notice was served preventing re-start until the mechanical integrity of the plant was ensured. The plant was shutdown for a number of weeks.



Example 3.7: Investigation (Chemical Processing)

Investigation of two toxic releases on a top tier chemical manufacturing site. Due to the potential for fatality, these constituted COMAH Major Accidents. There was, however, no site-wide or off-site risk. The company had already carried out its own detailed and comprehensive investigations into these incidents and identified remedial actions to address both immediate and underlying causes. HSE’s investigation was therefore largely limited to reviewing the company investigations and conclusions.

Example 3.8: Investigation & Enforcement (Health and Hygiene)

A business unit of a multinational chemical company primarily involved in the manufacture of active pharmaceuticals. Approximately 150 people are employed on site. A contractor carrying out hot work initiated a fire by working in close proximity to a new section of plant which was made of a flammable material. The resultant fire led to extensive damage to a section of the factory without causing personnel injury. The plume of smoke from the fire was blown towards a local housing estate causing concern and residents were advised to stay in doors. An improvement Notice was served.



Example 3.9: Investigation (Gas & pipelines)

An operator employing approximately 150 people, processing gas from North Sea production wells to supply natural gas and other product streams to the pipeline network. A gas release from a turbo-expander of the gas separation train occurred when a flange parted and the o-ring failed at a seal gas filter. There was no ignition of gas or injuries. This simple failure was investigated by company and HSE costs consisted of consideration of the operator's investigation report, a meeting to discuss findings and actions and to prepare a report on the conclusions.

Example 3.10: Derogation (Explosives Industry)

An operator which employs 30 staff machining depleted uranium [DU] billets for projectiles. Although depleted uranium is mildly radioactive it is also classified under CHIP as very toxic. The site holds more than 20T of DU. The hazardous installation is the billet and swarf storage facility. A substantial part of the inventory of DU comprises of billets in massive form. Operator rather than submit a site SR may apply for a derogation under COMAH Regulation7(12) on the basis that the metal is in such a form that it is incapable of creating a major hazard. A site visit was undertaken to see how much of the inventory is in 'massive form' and explain what the operator needs to include in their derogation application.

Example 3.11: Public Register

An operator which employs 40 staff manufacturing pesticide intermediates at a top-tier site due to the bulk chlorine storage and aggregation of toxics. The operator is a subsidiary of a multi-national chemical manufacturer involved with GM crops. The site is a potential target for certain activist groups and the operator requested that some information should withheld from the public register.

Example 3.12: Domino Effects

Typically simple establishments require approximately 0.5 hours to assess the Domino risk, but this can rise to approximately 7 hours for very complex sites.

Examples of COMAH work at Lower Tier sites

Example 3.13: Inspection (Petrochemicals Storage and Distribution)

A medium-sized lower-tier petrochemicals terminal employing 15 on site and 10 road tanker drivers. Pipeline import, bulk storage and road tanker distribution of gasoline, diesel and other fuel oils. Significant on and off-site fire hazards. Inspection includes examination of the implementation of MAPP/safety management system for the site and inspection of risk control measures. An intervention plan has been developed based upon a formal structured hazard assessment.

Example 3.14: Inspection (Chemical Processing)

A medium-sized chemical works with a large range of chemical manufacturing processes carried out at elevated temperature and pressure, with the associated storage of raw materials, intermediates and finished products. One hundred people employed on site. There are explosive, flammable and toxic hazards with potential for significant on and off-site effects and environmental damage. An inspection of the site's safety management system and selected risk control systems requiring the involvement of 3 inspectors.

Example 3.15: Inspection (Gases)

A site engaged in manufacturing and storing industrial gases and the filling and distribution of gas cylinders employing about 30 people. A range of flammable, oxidising and toxic gases are stored. The site is lower-tier by virtue of its flammable gas inventory.

The inspection programme has centred around a hazard assessment and has looked at the manufacture and storage of flammable & oxidising gases, concentrating on maintenance of safety and environmentally critical systems, and the permit-to-work system. The inspections encompassed both safety and environmental aspects.

Example 3.16: Inspection (Primary Plastics)

Inspection at a lower tier primary plastics site was focused on control of production, including control of transfers at bulk monomer and solvent tanks and control of polymerisation reactions. Issues identified during the initial inspection were followed up at a second visit.

Example 3.17: Inspection & Investigation (Chemical Processing)

The investigation of three loss of containment issues over 3 month period at a lower-tier COMAH site. There was a small hydrogen release together with two substantial releases of highly flammable liquids. However, the measures in place dealt with incident effectively. There was no damage or injuries and the incidents were reported as dangerous occurrences. The investigation involved input from THE AGENCY, regulatory and discipline specialist Inspectors from HSE. Significant weaknesses in the company safety management system were identified. Improvement Notices were served to secure appropriate improvements in the management systems.



Example 3.18: Inspection and Investigation (Primary plastics)

A lower-tier COMAH site manufacturing approximately 90,000 te low density polyethylene using low, medium and high pressure ethylene from on site high pressure pipelines fed from an adjacent chemical site. Approximately 45 staff are employed on site, including contractors/visitors.

The inspection programme included assessment of the plant, process, software change procedures. The operator had set up a project to replace the old software system of plant control with a new distributed control system and during the changeover, a number of incidents occurred due to failures in this system.

There were 5 releases of hydrocarbon on site, and all but one of these related to failures in the distributed control system/changeover procedures. The other occurred when a bursting disc on a high-pressure ethylene compressor discharged, releasing 510 kg ethylene from a high-level vent. The plant control systems responded correctly and the plant was safely shutdown.



Example 3.19: Inspection, Investigation & Enforcement (Paints, Glues and Sealants)

A lower tier paint manufacturer employing 120. COMAH applies by virtue of a very toxic substance used as a paint additive. An initial inspection was undertaken to benchmark the standards for electrical zoning and control of ignition sources. This involved process safety, control and instrumentation specialist and regulatory inspectors.

Investigation and Enforcement

An investigation was carried out into a spillage of highly flammable liquid during paint manufacture. The spillage was safely cleared up without further incident. The investigation revealed that the company had not taken all necessary measures to reduce the risk of a major accident in that there were insufficient controls to reduce the risk of operators leaving both valves open at the end of the filling process which would result in a spillage. A COMAH Improvement Notice was served.



Example 3.20: Investigation (Storage and Distribution)

A lower-tier site operated by around 10 employees which includes the receipt, storage and loading by road, sea and rail of hazardous substances including methanol, petrol and diesel. The operator is a wholly owned subsidiary of an international company with several sites in the UK.

During a routine transfer of methanol to a road tanker approximately 5000litres was spilled at the loading bay. The loading operation was stopped and the men evacuated the area and the site emergency response was initiated. The methanol was directed to a safe place by on site personnel. The incident was investigated jointly by the Agency and HSE [CA].

Example 3.21: Investigation (Gases)

A release of hydrogen bromide gas occurred from a transportable gas cylinder stored on waste ground at a lower-tier site specialising in inspection, testing and re-filling of industrial and medical gases. Site employs approximately 85 staff. The release went off-site, resulting in an emergency response by the emergency services with members of the public being admitted to hospital. The investigation into the failure of the gas cylinder resulted in enforcement action.



Example 3.22: Investigation (Gases)

A small lower-tier COMAH site undertaking LPG cylinder filling. An investigation of a fire and explosion, which demolished the filling plant, following a release of propane was undertaken.

This involved two regulatory specialist Inspectors from the local field team, supported by a process safety specialist Inspector. A mechanical engineering discipline specialist, supported by HSL, inspected and reported on the condition of a pipe coupling.

Example 3.23: Investigation & Enforcement (Pharmaceuticals)

A large cosmetics manufacturer employing over 350 people in the batch manufacture of cosmetic products. There are several dangerous substances on site but it is lower-tier because of its 90 tonne inventory of extremely flammable substances used for aerosol propellants and as solvents. A notifiable dangerous occurrence happened when an LPG cylinder was damaged leading to the uncontrolled release of 500Kg of propane. There were no resulting injuries. The investigation focused on poor management systems. An Improvement Notice was served requiring the company to establish an adequate safety management system.



Examples of RSP Work

Example 3.24: Inspection and enforcement (legionella)

Inspection to assess legionella control measures at a site that has cooling towers. Following the inspection, an improvement notice to carry out suitable and sufficient risk assessment was served.

Example 3.25: Investigation (transport)

Investigation of an incident where an employee was injured when a fork lift truck reversed into him, crushing him between the truck and a pallet of drums.

Example 3.26: Investigation (transport/ machinery)

Investigation of an incident where an excavator overturned.

Example 3.27: Investigation (COSHH)

Investigation of an incident where an employee was exposed to sulphuric acid mist during tanker offloading

Example 3.28: Investigation (COSHH)

An employee suffered cyanosis due to exposure to aniline when changing a gasket flange. Issues identified included inadequate risk assessment and consequent failure to take proper precautions.

Example 3.29: Investigation (Fall from Height)

Investigation of an incident where an employee fell from a ladder and was injured.

Updated 2012-10-17