A positive legionella sample can be worrying, but it is not a reason to panic. It is a sign that your water system needs attention, and a good plan will help you act quickly and sensibly.
Step 1: Read the report carefully
Your laboratory report will say where samples were taken and what was found. Look at which outlets or parts of the system are affected. The report should be read alongside your legionella risk assessment, because the two together tell the full story.
Step 2: Get competent advice quickly
Contact whoever is responsible for managing your water system, and speak to a competent legionella specialist. They can interpret the result, look at your system and advise on immediate control measures. For healthcare settings, follow your organisation’s procedures and the HPSC national guidelines.
Step 3: Reduce the risk to people
Depending on the situation, your adviser may suggest short-term steps, such as restricting use of affected outlets or showers while you investigate. Take their advice seriously, particularly where vulnerable people are present.
Step 4: Find the cause
Common contributors include low use, stagnant water, poor temperatures, dead legs, dirty showerheads and tanks that have not been inspected. A site review will help identify what has gone wrong so it is fixed, not just treated.
Step 5: Carry out corrective action
This might include cleaning and disinfection, repairs, removing dead legs, adjusting temperatures or changing how outlets are flushed. Your specialist will advise on what is appropriate for your system.
Step 6: Re-sample and review
After corrective work, retesting shows whether it has worked. Update your legionella risk assessment, your written scheme and your logbook so the record reflects what happened and what changed.
Keep records
Write down who was told, what actions were taken, and when. Good records show that you responded properly.
Your duties
Under the Safety, Health and Welfare at Work Act 2005, employers must manage risks to health, and the HPSC guidance sets out how to control legionella in water systems. A prompt, documented response is the best way to meet those expectations.
We can help
Safer Solutions provides legionella risk assessments and sampling with an independent accredited laboratory. If you have had a result and are unsure what to do, call 086 275 9728 or email info@safersolutions.ie and we will talk you through the next steps.