436 Raising the Bar: Legionella Management & Industry Standards

With those words, Jemma Tennant highlights one of the most profound differences between Legionella management in Europe and the United States. In this episode of Scaling UP! H2O, host Trace Blackmore welcomes Jemma Tennant, Chair of the Water Management Society (WMSoc), to explore how legislation, enforcement, and professional training shape the fight against Legionella.  

Proactive Regulation and Duty of Care 

The UK treats Legionella as a foreseeable and preventable risk. Jemma explains how laws like the Health and Safety at Work Act and COSHH Regulations require mandatory Legionella risk assessments, temperature monitoring, and written control schemes—even when no cases have occurred. This contrasts with the U.S., where ASHRAE 188 serves as guidance rather than enforceable law, often triggering enforcement only after outbreaks. 

Jemma shares a case study where a housing association was fined £1.2 million despite no recorded illness, underscoring the UK’s proactive stance on protecting public health.

Hospitals, Design, and Emerging Challenges 

From hospital plumbing layouts to new “waterless” intensive care units, Jemma details how design choices can either mitigate or magnify waterborne risk. Scotland’s model of involving water safety groups at the design stage provides a proactive example for healthcare worldwide. She also outlines how climate change, net-zero initiatives, and rising ambient temperatures are complicating control strategies across Europe. 

Raising Standards Through Collaboration 

As Chair of WMSoc, Jemma is leading efforts to raise industry standards and reverse what she calls a “race to the bottom.” She describes partnerships with AWT in the U.S. and LMAG in Australia to share expertise across borders. The episode also explores her pursuit of the Certified Water Technologist (CWT) credential and her vision for adapting the certification for UK professionals. 

Conclusion 

This conversation is a call to action for water treatment professionals everywhere: regulations, standards, and collaboration matter. Whether in cooling towers, hospitals, or housing estates, Legionella management requires vigilance, shared knowledge, and a commitment to raising the bar. Listen to the full episode and discover how global collaboration can shape safer water management practices. 

Stay engaged, keep learning, and continue scaling up your knowledge! 

 

Timestamps

01:55 - Trace Blackmore introduces the final installment of Legionella Awareness Month 2025 

05:30 - Water You Know with James McDonald  

07:30 - Upcoming Events for Water Treatme