Frequently Asked Questions

Legionella is a bacteria that causes Legionnaires' disease, a severe form of pneumonia. It thrives in water systems at temperatures between 20–45°C, especially in stagnant or poorly maintained systems. Controlling legionella is critical to safeguarding public health and meeting legal obligations under health and safety law.

Legionella remedial works refer to corrective actions undertaken to minimize the risk of legionella bacteria in water systems. These include cleaning and disinfecting systems, replacing faulty components, eliminating dead legs, and upgrading system designs to prevent bacterial growth.

Failure to address legionella risks can lead to outbreaks of Legionnaires' disease, legal penalties, reputational damage, and breach of health and safety obligations under ACOP L8 and the Health and Safety at Work Act 1974. Delaying remedial works often leads to higher costs over time, as water systems can degrade further. This might require extensive repairs or complete system replacements in the future Completing Legionella remedial works is a proactive and necessary step to mitigate risks, reduce costs, and ensure safety. Investing in these measures saves organizations from expensive penalties, operational disruptions, and legal liabilities while protecting public health and the company’s reputation

If Legionella remedial works are not completed, organizations face escalating costs from emergency repairs, increased energy inefficiencies, and potential fines for non-compliance. Additionally, failing to address these issues allows bacterial growth to flourish, leading to a lack of control over water safety. This increases the risk of outbreaks, which can result in legal liabilities, reputational damage, and costly operational shutdowns. Proactive remedial works ensure financial predictability and maintain control over health and safety standards.

Yes, completing remedial works is part of the legal duty to control legionella risks as outlined in ACOP L8. Failure to act on identified risks breaches statutory obligations.

• Presence of dead legs or unused pipework. • Insufficient water flow leading to stagnation. • Inadequate temperature control (e.g., hot water not reaching ≥60°C). • Lime scale or biofilm build-up in water systems. • Poorly maintained or designed cold water storage tanks

Dead legs in water systems are sections of pipework where water flow is minimal or nonexistent, creating stagnant conditions. These stagnant areas provide an ideal environment for Legionella bacteria to grow and multiply, especially when the water temperature is within the bacteria’s thriving range (20–50°C). Dead legs are often overlooked, but they pose a significant risk by introducing contamination into the broader water system when water from these areas mixes with active flows.

1. Reduce Legionella Risk: Stagnant water in dead legs is one of the primary contributors to bacterial growth. By removing them, the water system maintains a consistent flow, reducing the chances of Legionella colonization. 2. Ensure Water Safety: Eliminating dead legs helps maintain a clean and safe water supply, ensuring that all areas of the system are flushed and bacteria-free. 3. Compliance with Regulations: Health and safety regulations, such as the HSE’s ACoP L8, emphasize the need to eliminate dead legs as part of an effective Legionella risk management plan. Non-compliance can lead to fines, penalties, and legal liabilities. 4. Prevent Long-term Costs: Addressing dead legs proactively can prevent costly outbreaks, emergency remediation efforts, and potential lawsuits. Regular maintenance and removal are far cheaper than managing the aftermath of contamination. 5. Improved System Efficiency: Dead legs can cause inefficiencies in water distribution. Removing them ensures better system performance and consistent temperature control, reducing energy costs and maintenance needs.

To prioritize Legionella remedial works, focus on addressing areas with the highest compliance and risk implications first. Begin by identifying high-risk features, such as dead legs, stagnation points, and improper temperature controls, as these are most likely to harbor Legionella. Prioritise actions that directly address regulatory compliance, such as those outlined in ACoP L8 or similar standards, to avoid fines and legal liabilities. By systematically addressing the most non-compliant and risk-prone areas, you ensure the safety of your water system while mitigating the chances of outbreaks and associated operational or legal consequences.

Remedial works are fundamental to achieving and maintaining long-term Legionella control by addressing underlying issues that contribute to bacterial growth. Actions such as removing dead legs, descaling, repairing faulty temperature controls, and improving system design eliminate areas of stagnation and conditions favorable to Legionella proliferation. These works also ensure compliance with health and safety regulations, reducing the risk of penalties and legal liabilities. Additionally, well-executed remedial works improve the efficiency and reliability of water systems, lowering maintenance costs and preventing expensive emergency interventions. By proactively addressing risks, remedial works provide a sustainable framework for controlling Legionella and safeguarding public health over the long term.