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Commercial Landlords Can Breathe Easier With A Plan To Protect Tenants From Legionellosis


The coronavirus has commanded the commercial real estate industry’s attention for the past couple of years, but it is not the only transmissible illness that poses a threat to tenants’ lungs.

Legionellosis is a potentially fatal disease that is particularly dangerous to the elderly, smokers or the immunocompromised. The Legionella bacterium is found worldwide but, fortunately, its means of transmission and ways to control it are well understood.

“This organism lives everywhere and is normally not harmful in small quantities for most people,” said Robert Miller, founder and president of water treatment company Earthwise Environmental. “But when it finds the right amplification method and host — specifically, immunocompromised people — Legionella creates a nasty pneumonia that people have trouble fighting.”

Unlike the coronavirus, Legionella bacteria are not spread person-to-person, but instead through a building’s water system.

Miller stressed that the risk isn’t in drinking the water — it is in inhaling the mist created by aerosol sources such as hot tubs, swimming pools and decorative fountains. In most commercial buildings, the biggest risk can be traced to air conditioning system cooling towers. If Legionella is present, it can be circulated throughout the building’s air ducts via mist produced by the cooling towers.

Miller said commercial landlords can remove the threat from their buildings with a water management program that identifies and then remediates Legionella sources. 

Minimum Legionella risk management requirements can be found in ANSI/ASHRAE Standard 188, which spells out the steps building owners and managers can take when designing, installing, operating or maintaining a centralized building water system. The Joint Commission earlier this year released its own guidelines on controlling the spread of Legionella specifically for healthcare buildings.

“The first step in writing a water management program, other than assembling a team of experts for your water management team, is to look at the water flow diagram in your building,” Miller said. 

The goal is to identify areas in the building’s plumbing system where water either has a chance to pool — which is where Legionella bacteria like to reproduce — or where mist is created.

Once the building has identified these potential problems, it can take steps to minimize risks, supported by ongoing monitoring.

“A management plan for a commercial office building might cost only $6K to create,” Miller said. “Once the plan is completed, you might have to perform $4K a year worth of tests to protect your tenants including any who might be immunocompromised. In the grand scheme of things, that's not expensive, particularly compared to the cost of potential litigation if people fall ill.” 

A range of secondary disinfection methods is available to help a building remove Legionella from its water system. These include chlorine dosing and ionization systems.  

Miller said Earthwise Environmental is agnostic about which of these secondary methods is better.

“Instead of promoting one particular approach, we like to talk to building managers about the pros and cons of each technology, as well as the maintenance required and the efficacy each system can provide. But many times, it's simply a matter of adding more chlorine to the water.”

While all commercial buildings should take steps to protect themselves, the threat of Legionellosis is most acute in hospitals, nursing homes and other healthcare settings that house large populations of vulnerable people. Miller has seen this firsthand at unprepared nursing homes that became the sites of fatal breakouts

Earthwise Environmental helps facilities develop water management plans to protect vulnerable residents. In the process, it can identify mitigation tactics that range from simply making sure all shower heads and faucets in patients’ rooms are regularly flushed to prevent a buildup of Legionella in pipes, to installing secondary treatment equipment.

“I have elderly relatives and friends of the family,” Miller said. “One of the questions I tell them to ask the nursing facility is ‘Do you have a water management plan? Do you know what's required to protect your residents?’”

Legionella was first identified in the 1970s when hundreds of mostly elderly men attending an American Legion convention at a hotel in Philadelphia fell sick, many of them fatally.

Miller said he follows protocols developed by Janet Stout, president of Special Pathogens Laboratory and research associate professor at the University of Pittsburgh Swanson School of Engineering. Stout was one of the first researchers to identify how patients like the Philadelphia conventioneers came in contact with Legionella.

Understanding of the illness has grown greatly in the past 30 years thanks to pioneers like Stout, Miller said, and building managers today can take simple steps to protect their occupants.

“This is such a low-cost investment,” he said. “You write a management plan, put it on file and you meet every quarter or six months via Zoom or a telephone call with your team to see if anything has changed and needs to be addressed. Most likely, nothing will come up as long as you follow the plan.”

This article was produced in collaboration between Studio B and Earthwise Environmental. Bisnow news staff was not involved in the production of this content.

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