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FAQs by Regulation

Reg 2 - Interpretation

1. What is the difference between a Top Tier and an Upper Tier establishment? Why has this changed?

Upper Tier is the terminology used in both the Seveso II and Seveso III Directives, although Top Tier was chosen for the guidance documents in COMAH 1999. We have chosen to use the term Upper Tier in COMAH 2015 because this achieves consistency in terminology with the Directive and is consistent with the government policy that where appropriate there should be implementation of Directives by ‘copy out’.

COMAH Regulations 2015 reference – 2(1)

2. What is the difference between a new, existing and other establishments?

A new establishment is an establishment that is constructed or enters into operation on or after 1 June 2015. A new establishment can also be a current establishment that changes tier due to modifications leading to a change in inventory on or after 1 June 2015, or a non COMAH site of operation which becomes a COMAH establishment due to an increase or other change in its inventory of dangerous substances.

An existing establishment is an establishment that was a Lower or Upper Tier site under the COMAH 1999 Regulations and continues to be a COMAH site at the same tier on 1 June 2015.

An other establishment is an establishment that was a Lower or Top Tier establishment under the COMAH 1999 Regulations but which changed tier after 1 June 2015, or a non COMAH site that become subject to the Regulations after the same date due to the change in the classification system from CHIP to CLP or because of a change in the CLP classification of an individual substance.

The crucial difference with an “other” establishment is that the change of tier of an establishment, or the coming into scope of a non COMAH site is because of changes outside of the control of the operator, and not linked to a change in inventory, process or activity. Other establishments will have longer to produce emergency plans and Safety Reports to reflect the nature of this change.

Further information on types of establishments can be found in Appendix 1 to L111.

COMAH Regulations 2015 reference – 2(1)

3. My site holds dangerous substances at quantities below the COMAH threshold. Could my site come into scope on the basis of anticipated presence in a loss of control scenario?

Possibly, yes. The intention of the Directive and the Regulations is that anticipated presence can affect a site’s COMAH status. This is because determining application of the Regulations to an establishment is intended to reflect the hazard that it is capable of posing to people and to the environment.

4. The Regulations say I have to consider dangerous substances that it is reasonable to foresee may be generated through loss of control. What does reasonable to foresee mean?

Reasonable to foresee is a concept in GB law. It covers a range of possibilities, but cannot be described by a fixed level of likelihood. GB law considers that it means something that an average person believes could or might happen.

Operators should consider what loss of control scenarios are possible before considering whether or not they are ‘reasonable to foresee’, this may include thinking about a scenario’s magnitude and potential effects, as well as the probability of it occurring. They may also seek advice from their COMAH Intervention Manager, although the onus remains on the duty-holder. If your site is not already in scope of COMAH, operators can contact the Competent Authority through the usual channels.

It must be acknowledged and accepted that there has to be an element of judgement involved in this consideration. This means that different conclusions may be reached in similar but different circumstances – this is legitimate and should not be viewed as inconsistency.

5. What kind of scenarios should I consider when calculating what substances it is reasonable to foresee that my site might generate through loss of control?

The L111 Guidance to the Regulations gives examples of process and storage scenarios that should be considered. Operators may choose to identify all possible scenarios then determine which of those it is reasonable to foresee. or example, when storing large quantities of two substances, which when mixed together could produce a noxious gas, consideration of proximity to each other of stored material, method of storage (e.g. large single volumes versus multiple small packages) and other relevant factors, could result in different conclusions.

Considerations will vary from site to site, and operators may wish to seek an opinion on their individual circumstance with their COMAH Intervention Manager. This may not always be a straightforward task but existing risk assessments produced under other Health and Safety legislation could be used as a starting point.

6. What help can the Competent Authority provide me with when calculating what substances it is reasonable to foresee that my site might generate through loss of control?

Operators may find it useful to seek the views of their COMAH Intervention Manager on how to carry out the task of identifying scenarios in which a loss of control is reasonable to foresee. Where a COMAH Intervention Manager provides any advice they will do so by taking into account the individual circumstances of the operator’s establishment.

Reg 3 - Application and Exceptions

7. Is fracking covered by these Regulations?

It is not anticipated that the process of fracking will come under these Regulations although that will be reviewed as the technology develops. It is possible that fracking sites could come into scope of other these Regulations due to using or storing relevant dangerous substances for uses such as cleaning or fuel.

8. Are pipelines covered by these Regulations?

The inventory of a pipeline within the boundary of an establishment must be included in the calculation to determine application of the Regulations. Any quantity of dangerous substances in a pipeline outside the establishment can be excluded.

9. My establishment is already in COMAH, do I need to do anything?

If you are already operating a COMAH establishment you should check the new Regulations and the accompanying legal guidance (link) to ensure that you are aware of changes between COMAH 1999 and COMAH 2015. All establishments will need to notify by 1 June 2016, ensure that their inventory of dangerous substances is expressed in CLP terms and comply with the new public information requirements. Upper tier establishments will need to consider what amendments are required to their safety reports. Although the changes between the two sets of Regulations have been kept to the minimum possible there are new and revised duties that all operators need to familiarise themselves with. Existing COMAH operators should already have been contacted advising them of what they need to do to comply with the new requirements, any existing establishments that haven’t been contacted should speak to their COMAH Intervention Manager.

10. I have heard that Article 4 of the Directive can be used to exclude a substance that doesn’t have major accident hazard potential. Is this true? Why isn’t this Article in the Regulations?

Article 4 of the Directive outlines a process for the European Commission to assess substances that may not have major accident hazard potential against set criteria. The criteria sets a very high standard that it should be impossible in practice to for a dangerous substance to create a major accident. A request or notification to review a substance will be submitted by a Member State but normally triggered by an industry or trade association. If the Commission thinks that the proposal is justified it can make a legislative proposal to the European Council and Parliament for the substance to be excluded from the scope of the Directive. Any proposal will be voted through the Qualified Majority Voting system. There is no scope in the Directive for an individual Member State to exclude a substance from scope unilaterally, bypassing this process. As any proposal to exclude a substance would need to go through the legislative process support from other Member States will be required.

The Article has not been transposed into national legislation as it does not place a duty on the Member State, the duty is on the Commission to assess any notification received.  Any industry or trade association who think they have a substance that should be considered for exemption should contact the Competent Authority to open discussions with a view to developing a proposal, where appropriate.

11. Do the COMAH Regulations 2015 cover waste? I have been told that waste is exempt from the Seveso III Directive and the COMAH Regulations.

Waste or waste products collected for reprocessing may come within the scope of COMAH where it is likely to possess equivalent properties to dangerous substances in terms of major accident potential. Note 5 of Part 3 of Schedule 1 to COMAH requires that in this situation it should be provisionally assigned to the most analogous CLP category.

COMAH Regulations 2015 reference – Schedule 1 (Note 5)

12. Do the COMAH Regulations apply to licensed nuclear sites

Yes they may, however there are two exceptions. First, hazards creating by ionising radiation originating from substances are excluded. Secondly, substances that create a hazard from ionising radiation but have other dangerous properties of the types listed in Part 1 of Schedule 1 to the regulations are excluded from scope if present on a licensed nuclear site. If a licensed nuclear site is in scope of these Regulations then its Competent Authority will be the Office for Nuclear Regulation (ONR) and the appropriate environmental agency.

COMAH Regulations 2015 reference – 3(2)(b) and (c)

Reg 6 - Notifications

13. My establishment has been in scope of COMAH 1999 for a number of years, why do we need to notify under the new Regulations ?

COMAH 2015 requires all establishments, including existing establishments to notify.  Notifications under COMAH 1999 contain inventories of dangerous substances expressed in terms of CHIP, as this is replaced by CLP in the 2015 Regulations the previous inventory  information will no longer be relevant. The notification form can be found on HSE’s website.

COMAH Regulations 2015 reference – 6(4)

14. If new data on the properties of substances becomes available that leads to a change to a company’s COMAH status, what should a company do?

Companies have a duty to classify the dangerous substances they use or store and to consider whether COMAH applies to their establishment and whether any changes to a substance’s classification affects that.  If a reclassification leads to a change in tier companies should complete a notification form with the appropriate information and comply with the relevant duties. The notification form can be found on HSE’s website.

COMAH Regulations 2015 reference – 6(6)

Reg 9 - Requirements relating to the preparation of safety reports

15. Will sites that were Top Tier sites under COMAH 1999 need to redo their safety reports? If so, what will be the timescales for completing this?

The Regulations require existing upper tier establishments to review their safety reports and submit any changes that may be required by the new regulations. Safety reports for all existing Upper Tier establishments must be compliant with these Regulations by 1 June 2016.  The amount of revision required will be dependent on the amount of change generated by the new Regulations such as reclassification of dangerous substances leading to new major accident scenarios.

COMAH Regulations 2015 reference – 9(2), (4) and (6)

For further information on preparing Safety Reports please refer to Part 3 of the L111, 3rd Edition – A guide to the COMAH Regulations 2015.

Reg 12 - Preparation, review and testing of internal emergency plans

16. I have heard that lower tier establishments will need to produce internal emergency plans. Is this true and if so, what is required?

The requirements for emergency planning for Lower Tier establishments have not changed in these Regulations.  Lower Tier emergency planning needs to taken into account in the Major Accident Prevention Policy (MAPP) and the Safety Management System (SMS). The requirement to include appropriate information on emergency planning in the SMS has been made clear in Schedule 2 of these Regulations.

COMAH Regulations 2015 reference – Schedule 2(2)(e)

Reg 14 - Review and testing of external emergency plans

17. Why has a duty been introduced compelling Category 1 responders to participate in the testing of external emergency plans?

During both formal and informal consultation on transposing the Seveso III Directive into domestic legislation it was suggested that some testing of external emergency plans in some instances was hampered by some Category 1 responders (as defined by the Civil Contingencies Act 2005) not participating.  This reduces the efficacy of the test and potentially wastes the resources of other attendees.  This requirement therefore allows the local authority to request attendance where it is considered necessary for the external emergency plan to be tested fully, and the designated authorities must then cooperate.  It is expected that this duty will be applied in a pragmatic way and involve dialogue between all involved parties to reach a mutually convenient outcome.

COMAH Regulations 2015 reference – 14(5) and (6)

Reg 17 - Provision of information to the public

18. Do the public information requirements mean that my safety report will have to be online?

No. There is no requirement for safety reports to be made permanently and electronically available under these Regulations.  This regulation requires all operators to provide basic information about their establishment/site such as what they do, what kind of substances they hold, what kind of major accidents could happen, what is done to prevent them and how the public is informed. This information will be hosted on a database on HSE’s website.

COMAH Regulations 2015 reference – 17(1) and (2)

19. What's happening to the public register?

There is no requirement under these Regulations for a public register. Any information currently held on the public register under COMAH 1999 will be removed and disposed of appropriately.  The requirement to make certain information permanently and electronically available to the public is not a direct replacement for the public register.

Reg 18 - Provision of information to persons likely to be affected by a major accident at an upper tier establishment

20. Why do Upper Tier operators still have to produce PIZ information if the information will be on available online under Regulation 17?

The requirement to provide information to persons likely to be affected by a major accident differs from the general information available to all members of the public in that it should be available to those who may be affected and they should not have to search for it or request it. The information provided to persons likely to be affected may also be more detailed or specific such as specific actions to take in the event of major accident.

COMAH Regulations 2015 reference – 18(1)

21. Can Upper Tier operators provide a link to the public information website to discharge the duty under Regulation 18 to provide PIZ information?

No. Whilst a good starting point the information provided under Regulation 17 will not be sufficient to meet the requirements of ‘PIZ information’. Due to its specific nature PIZ information should be tailored to include relevant information not required by the general public such as specific actions to take in the event of major accident.

COMAH Regulations 2015 reference – 18(1) and (3)

Reg 19 - Provision of information pursuant to a request

22. What kind of information about my establishment will members of the public be able to request ?

All information held by the Competent Authority concerned with the application and regulation of these Regulations is classed as Environmental Information and therefore can be requested by a member of the public under either the Environmental Information Regulations in England and Wales or Environmental Information Regulations (Scotland).  There are exceptions and exemptions within these Regulations allowing the Competent Authority to refuse to release information in certain circumstance such as national security, commercial or personal confidentiality.

COMAH Regulations 2015 reference – 19(1)

23. How will issues of commercial sensitivity and national security be dealt with under the new Regulations?

The regulations that cover the release of environmental information provide  exceptions under which  release of information in certain circumstance may be refused.  This includes where the information has implications for national security or commercial confidentiality.

24. What should I do if I think there is information that the Competent Authority holds about my site that should not be released to a member of the public?

Operators should inform the Competent Authority at the time of providing information of anything that they do not think should be made available on request.  This will not be considered by the Competent Authority at the time of receipt but will be taken into consideration if a request for information is received.

COMAH Regulations 2015 reference – 19(1) and (2)

25. Will there be guidance on what kind of information in my safety report should be marked as not suitable to public release?

Yes, and this guidance will have input from other parts of government concerning national security. Operators who have contact with NaCTSO officers should continue to discuss this topic with them.

Reg 24 - Domino effects and domino groups

26. The Regulations talks about neighbouring establishments, how are these different from Domino sites?

Domino sites are establishments in groups identified by the Competent Authority where the nature of the establishments could increase the risk or consequences of a major accident.

As well as ‘neighbouring establishments’ the regulations refer to ‘sites of operation’ falling outside the scope of the regulations.  These are references other premises which could be the source of or increase the consequences of a major accident.  Operators should consider neighbouring sites and their potential impact on their major accident hazard scenarios as part of their duties under these Regulations.

COMAH Regulations 2015 reference – 24(1) and 2(1)

Schedule 1 - Dangerous Substances

27. My establishment holds named and non named substances that fall into the same hazard category, how do I carry out the aggregation calculation?

Where a substance is named in Part 2 the threshold given in column two or three should be used to carry out the aggregation calculation regardless of whether or not the establishment holds other non-named substances in the same hazard category.

For example, an establishment holds 10 tonnes of Acetylene (named substance entry 19) that has a Lower Tier threshold of 5tn and an Upper Tier threshold of 50tn.  Acetylene has the hazard classification of Flammable Gas Category 1.  The establishment also holds 20 tonnes of other substances classified as Flammable Gas Category 1 not named in Part 2.  Flammable Gas Category 1 has a Lower Tier threshold of 10tn and an Upper Tier threshold of 50tn.  The establishment would be a Lower Tier establishment on the grounds of holding more than 5tn of Acetylene and more 10tn of other substances classified as Flammable Gas Category 1.  However a further calculation is required as  aggregation may make it an Upper Tier establishment.

The calculation would be;
10 ÷ 50 (quantity of acetylene ÷ upper threshold for acetylene) = 0.2
20 ÷ 50 (quantity of unnamed Flamm. Gas 1 ÷ upper tier threshold for P2) = 0.4
0.2 + 0.4 = 0.6 – The site does not reach the Upper Tier threshold

28. My establishment holds a substance in the named carcinogen list at entry 33 of Part 2, how should these be aggregated?

The substances listed in entry 33 of Part 2 as named carcinogens should be aggregated in the same way as any other named substances; grouping the relevant hazard classifications and using the thresholds in Part 2. The difference, as this is a list of different substances, is that an establishment holding more than one substance from this list may need to include them in different calculations.

For example - 2-naphthylamine has the classification of Hazardous to the Aquatic Environment Chronic Category 2 and should therefore be aggregated with any other dangerous substances falling within the Environmental (E) hazard group, whereas dimethyl sulphate is Acute Toxic Category 2 and should therefore be aggregated with any other dangerous substances falling within the Health (H) hazard group.

The named carcinogens can also be added together to determine applicability of the Regulations regardless of hazard classifications, for example a site hold 0.3tn of - 2-naphthylamine and 0.2tn of dimethyl sulphate would be in scope of these Regulations at Lower Tier on the basis of meeting the 0.5tn threshold despite the substances having different hazard classifications.

29. My establishment holds some named substances that don’t have any hazard classifications in the list in Part 1, how should they be aggregated?

Such substances should not be included in any aggregation calculations.

30. What substances and mixtures qualify under the entry for ‘Alternative Fuels’ in point (e) of entry 34?

To qualify as an alternative fuel a substance must be destined for use as fuel and show similar hazard properties to the other petroleum products in entry 34 which would typically be classification as a as "flammable liquid" and/or as "hazardous to the environment chronic 2". Substances that have a higher flammability or are more hazardous to the environment cannot qualify as alternative fuel.

This definition would suggest that alternative fuels must be liquid since gases and solids would have different properties as regards to flammability. Fuels that consist of substances named in part 2 of Annex I (e.g. methanol) and mixtures thereof (if remaining within the concentration limits set according to the properties of methanol under the CLP Regulation) cannot qualify as alternative fuel because, where a substance can qualify for more than one specific named substance entry, the one with the lowest thresholds shall apply.

31. Does the 2% rule apply if my establishment stores dangerous substances in small vessels each well below the 2% threshold?

Yes the Regulations would apply. The total quantity would need to be determined, the size of the storage would not be relevant in determining application of the Regulations.

32. What separation distance would be considered sufficient to demonstrate that a substance could not initiate a major accident on the establishment, therefore allowing the 2% rule to be applied?

A risk assessment will be required to determine whether or not the dangerous substance could initiate a major accident elsewhere on the establishment. This assessment could include factors such as the hazardous properties of the substances involved, the potential major hazard scenarios, mitigation measures and separation distances. As this assessment will continue a significant number of variables, there are no fixed separation distances.

Schedule 3 - Minimum data and information to be included in a safety report

33. Annex II says I have to include in my safety report a ‘review of past accidents and incidents with the same substances and processes used’. How wide will operators be expected to take this? This could mean a lot of extra work.

Sites will be required to provide this information within reason and with consideration to what is practical and relevant. For example lessons learned from other sites or countries should be taken into consideration where they are relevant to a process or substance used by the operator and its major accident hazard potential.  A source of information for this could be the eMARS database (the Major Accident Reporting System) which contains reports of chemical accidents and near misses.  This database contains reports from EU, UNECE and OECD countries.

Updated: 2016-01-06