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HSEGuidance

Water Management

Publisher
HSE · UK Health and Safety Executive
Type
Guidance
Date
Unknown
Themes
Hazardous SubstancesOccupational Health

Summary

HSE inspection guide on offshore potable water management, covering legionella control, water system risk assessment and dutyholder performance assessment.

Summary written automatically from the title and document text.

Themes: hazardous substances, occupational health.

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OFFSHORE MAJOR ACCIDENT REGULATOR

Offshore Petroleum Regulator for Environment & Decommissioning

The Offshore Water Management Inspection Guide Open Government Status Fully Open

Publication Date November 2025

Review Date November 2028

Review History Date Changes

November 3 Yearly review 2025

The review history should be used for any post publication reviews/changes

Target Audience OMAR Inspectors / ED Offshore Inspectors / ED Specialist Inspectors

Contents Summary.......................................................................................................................................... 2 Introduction ...................................................................................................................................... 3 Relevant Legislation ......................................................................................................................... 3 Action ............................................................................................................................................... 6 Background ...................................................................................................................................... 6 Other relevant Inspection Guides..................................................................................................... 7 The Offshore Health Risk Management Inspection Guide ............................................................... 7 Specialist Advice .............................................................................................................................. 7 Organisation..................................................................................................................................... 7 Targeting ...................................................................................................................................... 7 CM9: 2022/108073 Owner: ED5 Industrial Hygiene Page 1 of 21

Timing........................................................................................................................................... 8 Resources .................................................................................................................................... 8 Recording & Reporting ................................................................................................................. 9 Health and Safety ......................................................................................................................... 9 Appendix 1 – Plan, Do, Check, Act for Potable Water Management ............................................. 10 Appendix 2 – Success Criteria for Control ..................................................................................... 12 Appendix 3 - Application of EMM and Duty holder Performance Assessment ............................... 13

Summary This IG outlines an approach to the inspection of duty holder’s arrangements with respect to offshore potable water management and the key areas that inspectors should consider when inspecting this topic. It also sets out the criteria for satisfactory and unsatisfactory performance factors against which duty holder performance will be rated. Reference is made to technical standards and guidance that inspectors will use to form and opinion of legal compliance. The effectiveness of such systems is a key component of occupational health risk management and securing effective control of health risks to prevent or minimise the incidence of occupational diseases.

The Health and Safety at Work etc Act 1974 (the HSW Act), the Management of Health and Safety at Work Regulations 1999 (the Management Regulations) and the Control of Substances Hazardous to Health Regulations 2002 (COSHH) require duty holders to identify risks associated from potable water, namely from exposure to legionella bacteria (the causative agent of legionellosis, including Legionnaires’ disease) and other water borne pathogens and to either prevent, or where this is not reasonably practicable, adequately control exposure to these biological agents.

To comply with their legal duties, duty holders should: (a) identify and assess sources of risk. This includes checking whether conditions will encourage bacteria to multiply (b) if appropriate, prepare a written scheme for preventing or controlling the risk (c) implement, manage and monitor precautions – if control measures are to remain effective, regular monitoring of the systems and control measures is essential (d) keep records of the precautions (e) appoint a competent person with sufficient authority and knowledge of the water system to help take the measures needed to comply with the law

Duty holders are further required to ensure that an adequate supply of clean wholesome drinking water is available at suitable locations on an offshore installation, and the purity of the water supply is maintained and that such locations are clearly marked to show that drinking water is there.

Introduction The purpose of this IG is to provide information and guidance to OMAR inspectors to support the delivery of consistent and effective inspection of dutyholder arrangements to ensure compliance with relevant statutory provisions and promote effective health risk management. This IG highlights key areas for inspection and provides a framework against which inspectors can judge compliance, assign performance ratings, and determine what enforcement action should be taken with respect to legislative breaches that may be found.

Typical offshore water systems include • all water transfer equipment (eg bunkering hoses) • water makers • storage facilities • distribution pipework • utilities • ancillary plant and equipment such as pumps and water softeners etc.

The operational guidance outlines HSE’s priorities for inspection of COSHH risks offshore. It is important to note that this guidance does not include detailed information on other offshore health risks such as COSHH, Noise, Vibration, Asbestos, Ergonomics/Manual Handling, Ionising and Non- Ionising Radiations, Thermal Environment, Personal Protective Equipment, Food Hygiene, First-Aid and Welfare, which continue to form part of the remit of the ED Industrial Hygiene Team.

Relevant Legislation

Health and Safety at Work etc Act 1974 Section 2(1) It shall be the duty of every employer to ensure, so far as is reasonably practicable, the health, safety and welfare at work of all his employees.

Section 3(1) It shall be the duty of every employer to conduct his undertaking in such a way as to ensure, so far as is reasonably practicable, that persons not in his employment who may be affected thereby are not thereby exposed to risks to their health or safety.

Section 6 Places duties on any person who designs, manufactures, imports or supplies articles and substances for use at work to ensure these articles and substances are designed, constructed and tested and that it will be safe and without risks to health at all times when it is being set, used, cleaned or maintained by a person at work

The Management of Health and Safety at Work Regulations 1999

Regulation 3 Requires every employer shall make a suitable and sufficient assessment of the risks to the health and safety of his employees to which they are exposed whilst they are at work; and the risks to the health and safety of persons not in his employment arising out of or in connection with the conduct by him of his undertaking,

Regulation 5 Requires employers make and give effect to such arrangements as are appropriate, having regard to the nature of his activities and the size of his undertaking, for the effective planning, organisation, control, monitoring and review of the preventive and protective measures.

The Control of Substances Hazardous to Health Regulations 2002

Regulation 6 Requires employers to not carry out work which is liable to expose any employees to any substance hazardous to health unless he has made a suitable and sufficient assessment of the risk created by that work to the health of those employees and of the steps that need to be taken to meet the requirements of these Regulations; and implemented the steps.

Regulation 7 Requires employers to prevent, or where this is not reasonably practicable, adequately control, the exposure of any employees to substances hazardous to health.

Regulation 8 Requires employers who provide any control measure, other thing or facility in accordance with these Regulations to take all reasonable steps to ensure that it is properly used or applied as the case may be.

Regulation 9 Requires employers to maintain, examine and test control measures and, at suitable intervals review and, if necessary, revise those measures.

Regulation 12 Requires every employer who undertakes work which is liable to expose an employee to a substance hazardous to health provide that employee with suitable and sufficient information, instruction and training.

The Offshore Installations (Offshore Safety Directive) (Safety Case etc) Regulations 2015

Regulation 16 Requires a duty holder who prepares a safety case pursuant to these Regulations demonstrate that the duty holder’s management system is adequate to ensure that the relevant statutory provisions will, in respect of matters within the duty holder’s control, be complied with.

Offshore Installations and Pipeline Works (Management and Administration) Regulations 1995

Regulation 17 Requires duty holders ensure that an adequate supply of clean, wholesome drinking water is available at suitable locations on the offshore installation; and such locations are clearly marked to show that drinking water is there.

Legionnaires' disease. The control of legionella bacteria in water systems, the Approved Code of Practice (ACOP) L8 (Fourth Edition) This ACOP is aimed at duty holders, including employers, those in control of premises and those with health and safety responsibilities for others, to help them comply with their legal duties in relation to legionella. These include identifying and assessing sources of risk, preparing a scheme to prevent or control risk, implementing, managing and monitoring precautions, keeping records of precautions and appointing a manager to be responsible for others.

Action Inspectors should review relevant documentation outlined within the IG prior to the installation visit and test compliance during the installation visit against the “Success Criteria” given in Appendix 1.

Inspection of this topic should include both inspection of the priority areas as well as an inspection of the overall policy, procedures and organisation for managing occupational health risks to establish a consistent and complete coverage of the topic. In inspecting individual topic areas, it may be necessary to have input from the relevant specialist inspectors where there are technical issues beyond the competence of the IMT inspector.

By the conclusion of the inspection, it should be possible to:

• have undertaken a targeted proactive inspection of the potable water system offshore • investigate concerns associated with a potable water system offshore • decide whether the measures in place were adequate to control the risk of exposure; and take any necessary enforcement action where these are deemed inadequate

When carrying out inspections covered by this IG inspectors should:

• assess duty holder responses against the success criteria in Appendix 2 • use the performance descriptors in Appendix 1 and 2 to: o determine the appropriate performance rating o the initial enforcement expectation o consider how and when the issues raised during an inspection are to be closed out

Background Inhaling Legionella bacteria can lead to a number of diseases, which collectively are termed legionellosis, the most serious of which is Legionnaires’ disease. Legionnaires’ disease is a potentially fatal form of pneumonia and everyone is susceptible to infection. Cases are more common in people over 50, smokers, individuals with underlying medical conditions, e.g., diabetes, lung and heart disease and those who are immunocompromised.

Legionella bacteria can readily colonise man-made water systems presenting a risk to health where use of the system gives rise to aerosol generation. Any water system may be become colonised;

however, larger outbreaks of Legionnaires’ disease have been associated with ECS such as cooling towers and evaporative condensers.

The latest edition of L8 ACOP and guidance ‘Legionnaires’ disease the control of Legionella bacteria in water systems’ gives advice on how the requirements of the Health and Safety at Work etc. Act 1974, the Control of Substances Hazardous to Health Regulations 2002 as amended (COSHH) and the Management of Health and Safety at Work Regulations 1999 (MHSW) are applied to the risk from exposure to Legionella bacteria.

The aim of occupational hygiene is to prevent or control exposure to health risks by recognising health hazards (physical, chemical, biological, and ergonomic), evaluating the risk and establishing appropriate control measures. Biological occupational health hazards may include Legionella and other water borne bacteria.

The essential requirements for managing occupational health are the same as those for any management system. Any sub-system for managing occupational health risks should therefore have the key features of an adequate management system i.e., policy, organisation, planning and setting standards, performance measures and auditing and review. Confirmation should be obtained that a recognised code, standard or body of guidance has been considered in determining the required performance of the occupational health management system.

Other relevant Inspection Guides The Offshore Health Risk Management Inspection Guide The Offshore Control of Substances Hazardous to Health Inspection Guide

Specialist Advice Specialist advice should be sought from ED Industrial Hygiene Team in circumstances when considering enforcement / debate over relevant standards on any aspects of potable water management.

Organisation

Targeting

Inspections should be planned to ensure that the necessary site personnel are available and arrangements can be made to facilitate physical inspection of the system(s).

Timing

Inspectors should undertake Inspections as part of the agreed Intervention Plan or as determined by the EDSLT.

Resources

Further guidance can be sought from:

Legionnaires’ disease. The control of legionella bacteria in water systems. Approved Code of Practice and guidance L8 (Fourth edition) www.hse.gov.uk/books/l8.htm

Legionnaires’ disease Part 2: The control of legionella bacteria in hot and cold-water systems, HSG274 Part 2 www.hse.gov.uk/pubns/priced/hsg274part2.pdf

Legionnaires’ disease Part 3: The control of legionella bacteria in other risk systems HSG274 Part 3 www.hse.gov.uk/pubns/priced/hsg274.part3.pdf

Guidelines for Environmental Health on Offshore Installations Oil and Gas UK issue 2 published 2019 https://oeuk.org.uk/

Guidelines for Environmental Health on Offshore Installations Oil and Gas UK, Guidelines Addendum – Potable Water Management, issue 1 published April 2024 https://oeuk.org.uk/

Managing the segregation and isolation of potable water systems on offshore installations Offshore Information Sheet 4/2010 https://webarchive.nationalarchives.gov.uk/ukgwa/20241206071830/https://www.hse.gov.uk/offsho re/infosheets/is4-2010.htm

Marine Safety Forum: Delivering Quality Potable Water to Offshore Installations, issue 3 published 2021 https://marinesafetyforum.org/

HSE Offshore COSHH Essentials OCE15: Potable water and legionella control www.hse.gov.uk/pubns/guidance/oce15.pdf

Recording & Reporting

The duty holder performance ratings should be entered on the Inspection Rating (IRF) Tab of the relevant installation Intervention Plan Service Order. Findings should be recorded in the post inspection report and letter.

Health and Safety

When conducting an inspection, the principles for mitigating the risk to staff are as follows: - • Sound training for the recognition and identification of risks • Understanding of roles and responsibilities • Planning and conducting site visits in accordance with HSE procedures

Inspectors undertaking inspections must be suitably trained and competent. The aim is to avoid the risk of exposure by carrying out your duties without entering areas where exposure to Legionella may occur. If you are in any doubt about the hazards you face or whether control measures are adequate to safeguard your own health and safety, you should withdraw from the area and seek advice from your line manager or an experienced colleague.

In some situations (e.g., offshore) you may have to use the duty holder’s hot and cold-water systems. If you are in this position, you need to assure yourself that the systems are properly managed, so you are not put at risk. If high counts of Legionella are found while you are on an offshore installation, you should follow the controls put in place by the duty holder and sought further specialist advice from ED Industrial Hygiene Team.

Appendix 1 – Plan, Do, Check, Act for Potable Water Management

PLAN 1. Is there is overall organisational Potable Water Management procedure in place? 2. Is there is a risk assessment (RA) specific to the potable water system being inspected in place? It is important that the RA considers the risk of the system as a whole, including all water transfer equipment (bunkering hoses/pumps etc), water makers, storage facilities, distribution pipework, utilities, ancillary plant and equipment such as pumps and water softeners etc. Many RAs are over-reliant on the water treatment programme. Whilst this is likely to be a vital component in controlling risk, inspectors should ensure that all aspects of the management regime are appropriately addressed. The RA should identify characteristics of the plant or its location that contribute to overall risk, such as the presence of dead legs, damaged or corroded hardware, condition of the incoming water source, predisposition to process and/or environmental contamination

To assist with assessing whether a RA is suitable and sufficient, a list of the most common key requirements when assessing risk associated with a hot and cold-water system, based on mechanical, operational, chemical and management aspects is available Appendix 2.1 of the Technical Guidance HSG274 Part 2 The RA should be carried out by a competent person. The United Kingdom Accreditation Service (UKAS) accredits companies in this field, in accordance with BS8580 ‘Risk assessments for Legionella control – Code of practice’. Accreditation may provide some assurance that the RA is suitable and sufficient, but inspectors should not rely on this and should use their own knowledge and judgement to form an opinion on the suitability and sufficiency of individual assessments

3. Is there a written control scheme specific to the potable water system being inspected in place? The written control scheme (WCS) sets out how controls are to be implemented and the organisational arrangements to ensure these are, and remain, effective. It is likely to comprise (or signpost to) system plans/schematics, the water treatment programme, cleaning/disinfection procedures, inspection and monitoring regimes. It should clearly describe the correct operation of the system, including shutdown procedures, operating cycles, maintenance frequencies and actions to deal with matters of concern, e.g., breakdowns, abnormal/unexpected test results and/or visual fouling/contamination. An effective WCS should be well-ordered and easy to navigate to enable the duty holder to check that the correct procedures are being followed and facilitate monitoring review. A template giving suggested headings and structure is given Appendix 2.2 of the Technical Guidance HSG274 Part 2. An effective WCS will usually be one that has been jointly developed with technical and practical input from competent service provider(s) and the duty holder. The WCS should also reflect the findings of the RA.

4. Are provisions in place for the adequate supply of clean, wholesome drinking water? Are they available at suitable locations on the offshore installation? Are such locations clearly marked to show that drinking water is there?

CM9: 2022/108073 Owner: ED5 Industrial Hygiene Page 10 of 21

DO 1. Have all persons who are responsible for the management of potable water onboard the offshore installation and have a duty in implementing the WCS received adequate instruction and training? Are suitable arrangements in place to allow for implementation and maintaining effectiveness of the WCS?

2. Have control measures detailed within the WCS been adopted? Are these managed accordingly at the set frequencies/durations?

3. Do appropriate management records exist for the control measures?

4. Is plant and equipment being maintained in good condition and therefore the risk is controlled to “as low as reasonably practicable” (ALARP)?

5. Is there adequate supply of clean, wholesome drinking water available at suitable locations on the offshore installation? Are such locations are clearly marked to show that drinking water is there?

6. Are there suitable arrangements in place for bunkering operations?

CHECK 1. Do records illustrate that the control measures are being managed accordingly and the control scheme remains effective?

2. Do control verification results i.e. chemical and microbiological analysis indicate the control scheme remains effective?

3. Are there monitoring systems for inspection, maintenance and testing of the facilities and equipment associated with potable water management?

4. Is there is a system in place to review the WCS at appropriate intervals?

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