🧪 Legionella Risk Assessment – Plas Heli Main Building
The Legionella Risk Assessment (LRA) for Plas Heli identifies and evaluates risks associated with the venue’s hot and cold water systems. It ensures compliance with HSE L8, HSG274 Part 2, and COSHH requirements, and confirms that appropriate control measures are in place to prevent the growth of Legionella bacteria.
This page summarises the scope, findings, control measures, monitoring regime, and record‑keeping requirements of the Legionella Risk Assessment for the main Plas Heli building.
0. Separate Legionella Assessment for Caban Heli
Plas Heli Cyf manages two separate buildings with independent water systems. A dedicated Legionella Risk Assessment has been completed for Caban Heli, reflecting its distinct water supply, heating arrangements, and occupancy profile.
View Caban Heli Legionella Risk Assessment
1. Scope of the Legionella Risk Assessment
The LRA covers all components of Plas Heli’s main‑building water system, including:
- Direct mains-fed cold water supply
- Biomass boiler hot water generation
- Backup gas boilers
- Hot water storage controlled by the Building Management System (BMS)
- Distribution pipework
- Washrooms, kitchen, bar, and operational outlets
- Seasonal or low-use outlets
Download Signed Legionella Risk Assessment (PDF)
2. Key Findings
The LRA identifies the following key points:
- Cold water is direct from the mains, eliminating tank-related stagnation risks.
- Hot water temperatures are automatically maintained by the BMS at safe levels (≥ 60°C stored).
- Pwllheli has soft water, so limescale formation is minimal and descaling is not required.
- Low-use outlets require periodic flushing to prevent stagnation.
- Dead legs or redundant pipework must be removed or monitored.
- Temperature monitoring is reliable due to automated BMS control.
3. Control Measures
Control measures implemented at Plas Heli include:
- BMS-controlled hot water storage to maintain safe temperatures
- Direct mains cold water to reduce stagnation risk
- Weekly flushing of low-use outlets
- Routine inspection of outlets and pipework
- Removal or monitoring of any identified dead legs
- Regular review of risk assessment findings
4. Temperature Monitoring
The Building Management System (BMS) automatically records:
- Stored hot water temperatures (≥ 60°C)
- Distribution temperatures
- Boiler performance
- Alerts for temperature deviations
Manual verification checks may be carried out periodically to confirm BMS accuracy.
5. Flushing Regime
Weekly flushing is required for:
- Low-use taps
- Seasonal outlets
- Event-specific temporary outlets
- Any pipework identified as a stagnation risk
6. Maintenance & Corrective Actions
Maintenance actions may include:
- Inspection of outlets and pipework
- Removal of redundant pipework
- Corrective action following temperature deviations
- Review of BMS alerts and logs
- Updating the risk assessment following system changes
7. Record Keeping
All water hygiene records must be retained for at least 5 years, including:
- Legionella Risk Assessment
- BMS temperature logs
- Manual verification checks
- Flushing logs
- Maintenance records
- Corrective actions
8. Review Frequency
The Legionella Risk Assessment must be reviewed:
- Every 2 years, or
- Following any significant change to the water system, or
- Following an incident or temperature deviation
Signed and dated version (PDF)