Legionella pneumophila bacterium

Legionella Filtration

What Is Legionella Filtration?

Waterborne pathogens, like Legionella, present a significant number of healthcare-associated infections (HAIs) affecting millions of people per year. Inhaling Legionella from water mist, vapor, or droplets can cause Legionnaires’ disease, a severe form of pneumonia. Filters that effectively retain bacteria, like Legionella, in the water ensure the delivery of clean drinking water and ice.

The risk of Legionella and other opportunistic waterborne pathogens is something we take very seriously. It’s why we focus heavily on providing industry-leading filtration as part of our integrated approach to water safety. Our point-of-use and in-line ultrafilters protect against bacteria like Legionella and other opportunistic waterborne pathogens, with options for both remediation and to aid in infection control.

Tips to Reduce Risk of Legionella

  • Perform a facility audit, identifying high-risk areas and critical control points like faucets, showers, ice machines, and drinking water fountains
  • Follow your water management program to monitor water-quality parameters and consider microbial testing; and
  • Consider FDA-cleared, 90-day, point-of-use ultrafiltration for bacteria (e.g., Legionella) at surgical sinks for quick deployment during a compromised water event

Benefits of Ultrafiltration Related to Legionella Control

Nephros Point-of-Use Filters for Infection Control

If sinks or showers report positive counts of Legionella or if an outbreak occurs, you need a solution that is both fast and reliable. Point-of-use infection control filtration is a cost-effective and easy-to-install solution to safeguard immunocompromised patients and continue patient care uninterrupted.

While many filters on the market today have a pore size small enough to capture and retain Legionella pneumophila, it’s important to choose a solution with a long life in the case of an outbreak. Our S100 point-of-use infection control filters feature 0.1-micron technology that offers effective protection from waterborne pathogens for 90 days. This long life allows Engineering, Facilities, and Plant Operations Managers the time necessary to implement and validate the results of a corrective action plan.

Nephros In-Line Filters for Infection Control

Facilities often overlook ice machines as a critical control point because they assume that Legionella cannot grow in cold conditions. However, not only can it survive freezing temperatures, ice machines generate heat during ice production and create an environment that promotes bacterial growth.

Most ice machines are filtered with sediment and carbon filters, but for areas with susceptible patients, the addition of a filter which retains bacteria, viruses, and endotoxins is critical for infection control. Our DSU-H in-line filter supports ice machine applications and features dual-stage, 5 nanometer (0.005 um) membrane technology. With a pore size that is forty-times smaller than most other commercially available pathogen filters, the DSU-H also provides effective protection for 180 days.

Where Is Legionella Filtration Used?

It’s important to have filters capable of bacteria retention (e.g., Legionella) installed on equipment that can expose patients to contaminated water during compromised water events; new construction; equipment replacements; and changes in water treatment, usage, or municipal water supply. Relevant equipment includes sinks, showers, ice machines, drinking water fountains, bottle fillers, decorative water features, and beverage-dispensing appliances.

Your Joint Commission- or CMS-compliant water management program should identify areas like bone marrow transplant (BMT), burn units, and oncology floors in which patients are most likely to be exposed to aerosolized water droplets and left vulnerable to infection. This approach will help you address control points where Legionella filters will bring the most benefit to your facility’s infection prevention program.

Legionella Filtration Technology

The hollow-fiber technology that has allowed us to support renal patients with effective filtration for dialysis water, also drives our FDA-cleared infection control filters. Tested to withstand high concentrations of waterborne pathogens, such as Legionella pneumophila, Pseudomonas aeruginosa, and Nontuberculous mycobacteria, our point-of-use and in-line filters offer the support needed to help facilities react and respond to water emergencies.

Legionella Filtration Solutions

If your healthcare facility is experiencing a Legionella outbreak, patient safety, quick remediation, and staying out of the headlines are major concerns. Nephros can provide the filtrations solutions to help put your mind at ease and navigate a challenging situation.

Outbreaks often result in a 90-day observation to perform contact tracing and identify critical control points in need of remediation. Our S100 point-of-use infection control filters for sinks and showers offer effective protection from waterborne pathogens for 90 days, allowing Facilities/Engineering Teams to implement corrective actions plans.

After corrective action, in-line filtration, like our SSU-H and DSU-H, can be installed on a variety of equipment as a programmatic approach to water safety.


Reducing the risk of Legionella and other opportunistic waterborne pathogens is critical for infection control. We understand the need for fast, reliable solutions during water emergencies.

We complement your needs with a variety of FDA-cleared filtration options, water evaluation services, facility audits, and educational resources for immediate and programmatic support.

Pathogen Risk

Learn more about Legionella pneumophila

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