304 - BOHS P901 – Legionella: Management and Control of Building Hot and Cold-Water Services

BOHS P901 – Legionella: Management and Control of Building Hot and Cold-Water Services is a Level 4 qualification. It enables learners to identify, assess, and control risks associated with the spread of Legionella bacteria in hot and cold-water systems.

What is the BOHS P901 - Legionella: Management and Control of Building Hot and Cold Water Services course?

The BOHS P901 – Legionella: Management and Control of Building Hot and Cold-Water Services course is designed by the British Occupational Hygiene Society (BOHS). It provides learners with the knowledge and skills needed to identify and mitigate the risks posed by Legionella bacteria in domestic type hot and cold-water systems. The accredited one day course covers what Legionella is, how it proliferates, how it spreads within man made water systems, and the measures required to reduce the risk of exposure.

The course also equips learners to support their organisation’s legal duties relating to Legionella risk control. This includes understanding and applying the regulatory requirements outlined in the Health and Safety at Work Act, COSHH Regulations, and the Management of Health and Safety at Work Regulations, all of which underpin employer responsibilities for controlling Legionella risks in hot and cold-water systems.

Benefits for Employers

  • Ensures compliance with UK legislation and recognised guidance for managing Legionella risks in domestic hot and cold-water systems.

  • Helps establish reliable procedures, reducing the likelihood of costly system shutdowns or emergency remedial works.

  • Effective control measures reduce the risk of Legionnaires’ disease, supporting a safe and healthy working environment.

Benefits for Learners

  • Gain a respected BOHS qualification relevant to careers in facilities management, health and safety, building management and occupational hygiene.

  • Build confidence in assessing and managing workplace Legionella risk, helping protect yourself and colleagues.

  • Learn what causes Legionella growth, how it spreads, and how to prevent its proliferation.

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The BOHS P901 – Legionella: Management and Control of Building Hot and Cold-Water Services course is ideal for anyone responsible for domestic hot and cold-water systems in the workplace, including:

  • Water system technicians and operatives

  • Managers and supervisors

  • Maintenance Staff

  • Legionella consultants

  • Occupational hygienists and health and safety managers

Entry Requirements: 

Candidates should have: 

  • Prior knowledge of controlling legionella risk in domestic hot and cold-water systems. Completing the P900 Foundation course would also fulfil this requirement. 

  • A basic understanding of the following HSE guidance documents: 

    • L8 (latest version), Legionnaires’ disease: The control of legionella bacteria in water systems 

    • HSG274 (latest version), Legionnaires’ disease Part 2: The control of legionella bacteria in hot and cold-water systems 

The BOHS P901- Legionella: Management and Control of Building Hot and Cold Water Services course can be studied in-house and is 1 day long (typically 6 hours of teaching).

The learning objectives for this course on divided based on course section. Upon completion of this course, the candidate will have a strong grasp of the following key areas:

1. Introduction and history of the organism 

  • The occurrence of legionella, sources and primary cause of growth in man-made water systems.  

  • Types and significance of the bacteria.  

  • The infection chain, susceptibility to infection, symptoms, treatment and prognosis.  

  • Health effects on exposed people.  

  • Review of data gathered by Public Health England (PHE) and others. 

2. Legislation and guidance 

  • Acts of Parliament.  

  • Approved codes of practice, regulations, HSE guidance notes, British Standards. Other industry accepted good practice sources of information. 

3. Risk assessment of systems 

  • Role of the named duty holder and responsible person(s).  

  • Definition of competent responsible person.  

  • Key components of the management and control systems.  

  • Design and operation of domestic type hot and cold water systems.  

  • Importance of schematic diagrams and sentinel outlets.  

  • Sentinel points on hot water systems with a circulation.  

  • Significance of dead legs, blind ends and inaccessible parts of the water system.  

  • Examples of other miscellaneous systems (e.g. emergency showers). 

4. Operational control 

  • Duties and responsibilities of responsible person(s).  

  • The role, risks and responsibilities when subcontracting part of the task of the control strategy. 

  • The written scheme of precautions, including routine temperature checks and routine condition inspection.  

  • Other control strategies: ionisation, ClO2, etc. 

  • The role of general bacteriological testing as part of the control strategy.  

  • Corrective or remedial actions.  

  • Record keeping, the details required for effective management control and retention of monitoring data. 

5. Outbreak investigation procedures 

  • The appointment and role of a Proper Officer and Incident Control Team.  

  • Definition of an outbreak.  

  • The roles of the investigating organisations (HSE, PHE, local authority).  

  • Control and Investigation phases.  

  • Interpreting the patterns of cases to trace the source; interpreting the microbiology to trace the source and the role of sequence-based typing (SBT). 

6. Record keeping 

  • Regulatory requirements for record keeping. 

7. Case studies 

  • Causes of recent Legionnaires’ disease outbreaks and the suspected water system sources. 7.0.2 Prosecutions. 

The syllabus for BOHS P901 is divided into 7 sections:

  1. Introduction and history of the organism

  2. Legislation and guidance

  3. Risk assessment of systems

  4. Operational control

  5. Outbreak investigation procedures

  6. Record keeping

  7. Case studies

The BOHS P901 - Legionella: Management and Control of Building Hot and Cold Water Services is assessed through a written exam:

  • 20 short answer questions

  • 1 hour exam duration

  • 0–4 marks available per question

  • No marks deducted for incorrect answers

  • Pass mark: 50%

After completing BOHS P901, learners often progress to further qualifications, including:

Many learners also progress into health and safety careers by studying the NEBOSH General Certificate, the global benchmark for health and safety training.