Is Your Building Safe After a Long Shutdown?

Post-Occupancy Water Safety Checks – Is Your Building Safe After a Long Shutdown?

Keep your building safe after a long shut down. As summer break approaches, many schools and commercial buildings will see extended periods of reduced water usage—or complete closure. While this downtime gives buildings a rest, it can also create ideal conditions for Legionella bacteria to grow, raising Legionella water safety concerns.

Before reopening your school, student accommodation, office or factory there’s one crucial question to ask:

Is your water system safe—and legally compliant?

Why Shutdowns Increase Legionella Risk in Water Systems

When water sits stagnant in pipes, tanks, and outlets:

• Temperatures can sit in the Legionella growth zone (20–45°C)
• Biofilm can form, sheltering bacteria
• Dead legs and rarely used outlets go unflushed
• Disinfection levels degrade without circulation

These conditions dramatically increase the risk of Legionnaires’ disease—a potentially fatal form of pneumonia spread through water droplets.

Who’s Most at Risk from Legionella Bacteria After Shutdown?

This is particularly urgent for:

• Schools, especially those closed for 6+ weeks
• Student Accommodation
• Care homes, with vulnerable residents
• Gyms and leisure centres, with showers are high risk
• Offices, where water outlets may have sat unused for a period of time

Remember: Legionella isn’t just a health risk—it’s a legal liability.

Post-Shutdown Water Safety Checklist Before Reopening Your Building

Here’s a checklist of post-occupancy water safety checks and actions every duty holder should consider.

1. Review Your Legionella Risk Assessment for Post-Shutdown Compliance
   If your last risk assessment was over 2 years ago—or the building’s usage has changed—it’s time for a new one. We’ll identify system risks and help you manage them under ACOP L8 and HSG274 guidance.
2. Flush Water Systems to Remove Stagnation and Legionella Risks
   Flush all outlets (taps, showers, WCs) for a set period to replace stagnant water. This includes infrequently used outlets that may not have been part of daily use.
3. Temperature Checks for Legionella Water Safety Compliance
   We test hot and cold outlets to ensure water is reaching safe temperatures (hot ≥ 50°C, cold ≤ 20°C).
4. Inspect and Clean Cold Water Tanks for Legionella Bacteria Control
   Cold water storage tanks and calorifiers should be inspected for scale, sediment, and bacterial buildup. Cleaning and disinfection may be required before occupancy.
5. Legionella Water Sampling for High-Risk Buildings
   In higher-risk buildings (care settings, previously positive sites), we can collect and lab-test water samples to check for Legionella presence.

Why Choose Irrigonics for Legionella Water Safety Services

We work with many businesses across the UK to keep buildings safe, legal, and ready for reopening.

1. ACOP L8-compliant Legionella risk assessments

2. Post-shutdown flushing & disinfection services

3. Digital reports & remedial action planning

4. Friendly, DBS-checked engineers

Whether you’re managing a single school or a multi-site trust, we make water compliance easy, clear, and audit-proof

Is Your Building Safe After a Long Shutdown?

Stay updated with the latest in water safety, compliance tips, and industry news.

Facebook – facebook.com/irrigonics
LinkedIn – linkedin.com/company/irrigonics
Instagram – instagram.com/irrigonics

Follow, like, and share to keep your network safe and compliant.

Does your business need a legionella risk assessment?

Back to the blog