Fresh from winning Product or Service Development at the IWFM Impact Awards 2026, PTSG Water Treatment says continuous remote monitoring is changing what Legionella compliance looks like. It also raises an uncomfortable question for the sector: if compliance only happens on visit day, what is happening the rest of the year?
Every year in the UK, around 500 people contract Legionnaires’ disease. It is a preventable illness. Yet in almost every case, the bacteria responsible had been sitting in a building’s water system for some time, undetected, because nobody was looking.
That is not a failure of diligence. It is a failure of design. For decades, Legionella compliance in facilities management has been built around the engineer visit: a qualified person arrives on schedule, tests temperatures at designated outlets, records the results and leaves. The building is compliant on that day. What happens between that visit and the next one is, in most cases, simply unknown.
From periodic checks to continuous monitoring
Remote monitoring replaces those snapshots with a constant flow of data. Wireless sensors fitted at outlets and key points in a water system record temperatures around the clock. They send readings to a cloud platform, which checks them automatically against safe limits. Duty holders no longer wait for the next scheduled visit to find out an outlet has drifted out of range. They know almost straight away.
This matters most in the buildings that are hardest to manage by hand. Sites with low or irregular footfall, unused outlets and stagnant water are the conditions that raise Legionella risk, and they are also the conditions a periodic regime is least likely to catch.
Built for UK compliance
PTSG Water Treatment designed its remote monitoring system around UK water hygiene regulation from the start. LoRaWAN sensors automatically report more often as temperatures approach unsafe limits. A cloud portal gives a live compliance view on any device, with audit-ready reports built for HSG274 and ACoP L8. Alert logic mapped to regulation flags what matters legally, such as an outlet left unused for seven days or more, before a manual regime would notice. Each installation uses the same core technology, with sensors and thresholds set to suit the individual building.
What it means for duty holders
The benefits go beyond convenience:
- Better compliance visibility: a live picture across a single site or a whole estate, rather than records that only show how things looked on the day of a visit.
- Proactive risk management: problems are flagged as they develop, so action can be taken before a risk grows.
- Less disruption on site: fewer routine visits just to take temperature readings means less disruption for building users. That matters most in sensitive environments where an unplanned visit has real consequences.
- A stronger audit trail: every reading is time-stamped and stored, giving a more complete compliance record than any manual regime can.
The harder question
The biggest barrier to adoption is not the technology but trust. Clients used to engineer visits are understandably sceptical that a sensor can carry the same legal weight as a person with a clipboard. Mapping every element of the system to HSG274, ACoP L8 and wider health and safety law, and producing a complete audit trail, changes that conversation. Once clients see continuous data, it is hard to go back to a reading that only proves a temperature was safe last Tuesday.
“Compliance that only happens on visit day isn’t really compliance. It’s a series of moments, and anything can happen in between,” says Craig Doig, Managing Director of PTSG Water Treatment. “Remote monitoring watches every outlet, every hour, without anyone needing to set foot on site. Winning this award tells us the sector is ready for that shift.”
Next, PTSG Water Treatment is developing predictive analytics to spot deterioration before thresholds are reached, alongside CAFM integration, flow monitoring and automated sustainability reporting.
For duty holders, the lesson reaches beyond one product. The sector has always asked “are we compliant?” The more useful question is harder: how would we know if we weren’t?
PTSG won the IWFM Impact Award 2026 for Product or Service Development for its Remote Temperature Monitor System. Read more about this year’s winners here.
