"Healthcare facilities serving immunocompromised populations—particularly bone marrow transplant (BMT) patients—require advanced water safety strategies that exceed typical regulatory expectations. This case study presents a proactive Legionella mitigation approach implemented during the renovation of a specialty hospital expansion housing a BMT unit. Recognizing the heightened susceptibility of these patients to waterborne pathogens, the project team integrated a comprehensive water management framework beginning early in the design phase.
Mitigation strategies included point-of-entry sub-micron filtration, high-temperature water generation with thermostatic balancing, engineered recirculation loops to minimize water stagnation, and elimination of dead legs. Advanced system controls were incorporated to maintain critical temperatures and monitor flow dynamics, supplemented by a secondary disinfection system selected based on a risk/benefit analysis of chemical compatibility, scalability, and impact on sensitive patient care equipment.
The case study demonstrates that embedding water safety risk mitigation into early design and construction activities improves system resilience, reduces startup contamination risk, and establishes a sustainable foundation for long-term waterborne pathogen control in environments serving highly vulnerable patient populations. This proactive model emphasizes multidisciplinary coordination among engineering, infection prevention, clinical leadership, and commissioning teams to achieve reliable Legionella control prior to patient occupancy."