Published July 2017

By Kelly A. Reynolds, MSPH, PhD

If you follow On Tap frequently, you know that the bacterium, Legionella, has been a repeated topic in recent years. Once again, Legionella is at the forefront of discussions due to continuing waterborne outbreaks and new directives in healthcare facilities for prevention. On June 2, the Department of Health and Human Services, Centers for Medicare and Medicaid Services (CMS) issued a memo that will undoubtedly expand the awareness of Legionella risks and further drive the implementation of preventative approaches.

Source: Water Conditioning & Purification Online

What the CMS Legionella Directive Means for Healthcare Water Systems

The 2017 Centers for Medicare & Medicaid Services memo marked a turning point in how healthcare facilities must approach water safety. For the first time, CMS explicitly required all Medicare- and Medicaid-certified healthcare facilities — including hospitals, long-term care facilities, assisted living centers, and dialysis clinics — to develop and implement water management programs specifically designed to reduce the risk of Legionella growth and transmission.

Legionella pneumophila is the bacterium responsible for Legionnaires’ disease, a severe form of pneumonia with a case fatality rate of 10–15% in the general population — and significantly higher in immunocompromised patients receiving care in healthcare settings. Outbreaks linked to hospital water systems, cooling towers, and hot tubs have been documented across the United States, with healthcare-associated Legionellosis cases representing a disproportionate share of total reported cases each year.

The CMS directive aligns with ASHRAE Standard 188, which provides the technical framework for water management programs. Under ASHRAE 188, facilities must identify all water system components where Legionella can proliferate, establish control limits for temperature, disinfectant residuals, and pH, implement monitoring and response protocols, and maintain documentation demonstrating ongoing compliance. Failure to comply can result in loss of Medicare/Medicaid certification — a financial and operational risk that no healthcare facility can afford to ignore.

How Legionella Grows in Building Water Systems

Legionella thrives in warm, stagnant water with temperatures between 77°F and 113°F (25°C–45°C) — a range that overlaps with many building hot water systems. The bacteria attach to scale, sediment, and biofilm within plumbing, cooling towers, hot water tanks, and decorative water features, making physical removal and chemical treatment both necessary components of any effective control program.

Healthcare facilities face particular challenges because their water systems are complex, with long distribution runs, multiple temperature zones, and patient populations that are most vulnerable to respiratory infection. Low-occupancy rooms with infrequently used fixtures create stagnant conditions ideal for Legionella amplification. Point-of-care water outlets — including ice machines, respiratory therapy equipment, and patient room sinks — represent potential exposure points that must be specifically addressed in water management plans.

AMPAC USA Water Treatment Solutions for Healthcare Legionella Control

AMPAC USA supplies water treatment systems that address multiple risk factors in healthcare water management programs. Our systems include point-of-use filtration units with 0.2-micron absolute ratings for Legionella removal at individual taps, ultraviolet (UV) disinfection systems for continuous inactivation of Legionella and other pathogens throughout water distribution lines, and supplemental treatment systems for hot water recirculating loops. These solutions complement chemical disinfection programs and provide physical barriers against pathogen exposure at the point of patient contact.

For healthcare facilities performing water system risk assessments under ASHRAE 188, AMPAC USA’s engineering team can evaluate existing water treatment infrastructure and recommend integrated solutions that address both Legionella control and broader water quality objectives. Our systems are designed to maintain consistent disinfection efficacy even during high-demand periods when water turnover is reduced in portions of the distribution system. Learn more at www.ampac1.com.