Test for Legionella.

Professional Legionella testing ensures your water system is managed safely and provides peace of mind for your family. For landlords in the UK, conducting a Legionella risk assessment is a legal requirement to ensure the safety of tenants.

What Does the Work Involve?

• System Survey: A technician inspects the entire water layout, including tanks, cylinders, and all outlets like showers and taps.
• Temperature Monitoring: Checking that hot water is stored above 60°C and cold water stays below 20°C to prevent bacterial growth.
• Sample Collection: Taking water samples from "sentinel" points (the nearest and furthest outlets from the heat source) using sterile containers.
• Laboratory Analysis: Sending samples to a UKAS-accredited laboratory to culture and identify any Legionella pneumophila strains.
• Risk Assessment Report: Providing a detailed document outlining findings, identifying "dead legs" in pipework, and recommending remedial actions.

Typical Costs

Prices vary based on the size of the property and the number of water outlets. Most technicians charge a fixed fee for the assessment, with additional costs for each lab sample required.

How Long Does It Take?

• On-site Assessment: 1 to 2 hours for a standard residential property.
• Lab Analysis: 10 to 14 days (Legionella cultures take time to grow in a controlled environment).
• Final Report Delivery: Usually within 48 hours of the lab results being finalised.

DIY or Professional?

While homeowners can perform basic temperature checks, a formal Legionella risk assessment and sampling must be conducted by a competent person. Laboratory testing cannot be done via DIY methods as it requires sterile handling and UKAS-accredited facilities to be legally or insurance-compliant.

Note for Landlords: You are legally responsible for the health and safety of your tenants. A professional assessment is the only way to prove you have fulfilled your "duty of care" under UK health and safety law.

Choosing the Right Tradesperson

• Check Accreditations: Look for membership in the Legionella Control Association (LCA) or City & Guilds qualifications in Legionella management.
• Lab Standards: Ensure they use a UKAS-accredited laboratory for all water analysis.
• Insurance: Confirm they hold Professional Indemnity insurance specifically covering Legionella works.
• Questions to Ask:
  • Do you provide a full written report with photographic evidence?
  • Are the lab fees included in your initial quote?
  • What is your procedure if a sample returns a positive result?

UK Regulations

• HSE ACOP L8: The primary Approved Code of Practice for the control of Legionella bacteria in water systems.
• HSG274: Technical guidance that outlines how to manage the risks in hot and cold water systems.
• Landlord & Tenant Act 1985: Requires landlords to keep the supply of water in repair and safe for use.

Common Problems

• Dead Legs: Lengths of redundant pipework where water stagnates, providing a breeding ground for bacteria.
• Low Water Heater Temps: Setting a boiler too low to save energy can allow bacteria to multiply rapidly (between 20°C and 45°C).
• Scale and Biofilm: Limescale buildup in showerheads provides nutrients and protection for Legionella.
• Infrequently Used Outlets: Guest bathrooms or outdoor taps that aren't flushed regularly are high-risk areas.

Frequently Asked Questions