The usual suspect

New legislation and regulations in New York focus on cooling towers, the likely culprit of the recent Legionnaires’ disease outbreak.

The New York City Council approved legislation on August 13 mandating several measures for cooling towers in the midst of the city’s worst breakout of Legionnaires’ disease that has sickened more than 100 people and killed 12.

“As the city works to ensure that everyone who is suffering from Legionnaires’ disease is getting proper treatment, we must also look to the source of the problem,” said Council Speaker Melissa Mark-Viverito. “We’re in the midst of a crisis in New York City, and this council is taking swift action to address what is happening.”

Mayor Bill de Blasio signed the legislation into law on August 19. Here are the measures to expect:

Building owners will be required to test the water in the towers every three months for Legionella, the bacterium that was first identified as the cause of death for 34 members of the American Legion as the group gathered at a Philadelphia hotel in 1976.

All cooling towers are to be registered with the city’s Department of Buildings within 30 days.

Building owners will be required to provide annual certification that their towers were inspected, tested, cleaned and disinfected.

Penalties for violations range from a $2,000 fine for first-time offenders and up to $10,000 if anyone is hurt or killed.

Business owners who fail to comply with a direct order from NYC public health officials face a year behind bars and a $25,000 fine.

The legislation follows a section of an ASHRAE standard, published just two months before the outbreak. That would be Section 7.2 of ANSI/ASHRAE Standard 188-2015, Legionellosis: Risk Management for Building Water Systems. In particular, Section 7.2 lists common tasks and steps for procedures such as new system start-up and seasonal shutdowns, general system maintenance, water treatment and disinfection plans.

In a search for answers, several NYC building officials called Ron George, CPD, president of Plumb-Tech Design & Consulting Services, as well as one of our magazine’s columnists.

“We discussed how an engineer can build an ideal system,” he told us. “But if such a system does not get maintained and disinfecting chemicals are not added, it can go septic.”

George suggested the officials take a look at existing ordinances, for example, which require backflow preventers to be tested annually or grease interceptors cleaned on a regular basis. In turn, required documentation assures these practices take place. He also passed on additional ASHRAE information and other reference points for cooling tower operations.

Maintenance of cooling towers is key, according to George, instead of the testing making the headlines.

“Testing for Legionella does not treat or prevent outbreaks,” he added, “it only confirms the presence and confirms the levels.”

Also, Legionella can be present in low levels, which neither indicates a serious problem nor the potential for an outbreak.

“Testing for Legionella is expensive and time-consuming,” George explained. “I believe it is faster and more effective to check for water treatment chemical residuals to make sure the water treatment chemicals are at a level that can control Legionella bacteria growth. Requiring building owners to provide documentation that show they are periodically cleaning and continually monitoring the building water system for water treatment chemical residuals is the answer.”

State response

Days after the council passed the legislation, Governor Andrew Cuomo adopted similar emergency regulations throughout New York for the state’s Department of Health.

“Our new emergency regulations will make sure that building owners live up to their responsibilities and provide health officials with critical information to counter the spread of Legionella bacteria,” the governor said. “I want to reassure all New Yorkers. We are addressing the problem at its source and protecting the public health statewide.”

The regulation are virtually identical with the city rules in that building owners must register their cooling towers, and are subject to civil and criminal penalties for failing to comply.

The emergency regulations will be in effect for 90 days, but then will be adopted as permanent regulations.

The recent efforts are a far cry from the he-said-she said politics of the previous week when the mayor and governor offered differing information at dueling press conferences at the same time that offered a conflicting picture of whether it was the city or the state that should regulate cooling towers. At one point, the governor wanted to call in the Centers for Disease Control and Prevention, a federal agency.

Not only weren’t the two on the same page, they weren’t even in the same library.

But even before the city’s legislation and the state’s regulations, the city had been on a break-neck pace to clean up all its cooling towers under an emergency order put into place August 6 that gave building owners two weeks to evaluate their towers.

Since the deadly outbreak of Legionnaire’s disease in the Bronx was discovered in July, 20 cooling towers out of more than 135 tested have been found to have the Legionella bacteria at last count.

There are thousands of cooling towers in NYC, So many, in fact, that there isn’t an official tally.

In an articled published by The New York Times on August 18, a managing partner for one firm that specializes in cleaning the cooling towers said his company was receiving 100 calls a day.

“The phone does not stop ringing,” said Greg Frazier, of Clarity Water Technologies. “Everyone has been sort of panic-stricken because of the deadline.”

Under industry standards, the process of disinfecting a tower can range from less than $1,000 to simply add chemicals to more extensive cleaning that be as much as $30,000.

Other sources?

While cooling towers are taking most of the blame for the NYC outbreak, at this point, no one has any conclusive proof of the actual source of the outbreak. Shower heads, whirlpool spas and decorative fountains can effectively spread the bacteria, too. However, exposure to the disease tends to be limited in such cases.

From George’s perspective, not only can cooling towers spread the disease much farther than a lobby fountain, it may only take one.

“It seems like they keep adding to the number of Legionella-infected cooling towers as they test them,” George said.

“They are focusing on cooling towers that were not properly maintained as the culprit for this latest outbreak,” George added. “However, the towers could have been seeding each other with bacteria. It only takes one poorly maintained cooling tower to bloom to high levels and then spread Legionella bacteria to neighboring cooling towers in the wind.”

George shared the following for cleaning up cooling towers: Perform “online” disinfection instead of “offline” cleaning and disinfection for emergency disinfection of contaminated cooling towers unless full physical cleaning is absolutely necessary at the time.

Online disinfection is simply adding or increasing the disinfectant chemicals to levels that kill all bacteria and organisms in the cooling tower basin. The online procedure involves only chemical disinfection while the cooling tower is operating and flowing condenser water throughout the condenser water system.

Although the online method does not address the physical cleaning of the cooling tower, it is effective in killing Legionella bacteria and all other organic pathogens in the cooling tower/condenser water system. Disinfecting online also keeps the cooling system on and it is is much safer, because you do not send workers into a contaminated basin to clean it. It is also less corrosive. A typical online disinfection basically amounts to maintaining a free chlorine concentration of approximately 5 parts per million for at least six hours.

The offline procedure involves shutting down the cooling tower (and, hence, the HVAC system) and scrubbing the cooling tower physically in addition to disinfecting it with chemicals.

A full offline disinfection and cleaning is typically done in the spring prior to bringing the cooling system on-line. Offline cleaning is more thorough, but is expensive.

More information on the method can be found in the Cooling Technology Institute’s publication Legionellosis Guideline: Best Practices for Control of Legionella, which can be downloaded free at

If a building owner, however, prefers to use the offline method, George recommends the following:

Provide personal protection equipment for the workers cleaning cooling towers. Respirators will reduce their risk of inhaling Legionella bacteria. Boots, protective clothing, and goggles will help protect their eyes and skin from chemicals.

Close building outdoor air intakes within the vicinity of the cooling tower. The CDC has recommended closing intakes within 30 meters of cooling towers undergoing cleaning operations.

Follow industry standards. Check with organizations such as the Cooling Technology Institute, ASSE publications, ASPE publications and the American Society of Heating, Refrigerating and Air-Conditioning Engineers for their latest recommendations. Follow instructions on chemical product labels. Keep records of the procedure, including the chemicals used, the time the chemicals were added to the system, and chlorine and pH test results. Be sure to follow all EPA and other applicable regulations and observe safety precautions. Utilizing a highly qualified and experienced water treatment specialist is the best way to ensure proper protocol is followed.

Finally, understand the limitations of either procedure. Building owners should have a “water management plan” in place to address and control potential hazards within the building water systems since studies have shown that Legionella bacteria may re-emerge within only days after fully disinfecting a cooling tower.

A program of regular water treatment, maintenance, and inspections provides better protection than periodic disinfection. A water management plan develops a team of qualified individuals to conduct a building survey and develop a water management and control plan including a flow diagram of all water systems in the building. The plan identifies all potential hazards like dead legs, water stored at temperatures ideal for bacteria growth, and potential sources of aerosolization of the water droplets, etc.

Then, develop a plan for corrective actions for each potential problem area. The water management plans apply to cooling towers, plumbing systems, hot tubs, swimming pools, decorative fountains and other water systems that can grow and transmit Legionella — the best protection is to implement a water management plan following ANSI/ASHRAE Standard 188-2015.

Meanwhile, ASHRAE will continued to urge passage of its full standard in New York City and other locations.

Michael Patton, a member of the committee who wrote the standard, told the NYC Council as it deliberated on its legislation that other sections also would play a role in reducing risks.

“Section 7 is very good by itself,” Patton testified, “but it doesn't really address the whole idea of informing building owners, managers, property managers how to put a plan for a whole building into place and what it should contain.”

Not surprisingly, the larger standard echoes much of George’s recommendations. Specific requirements in the standard include:

Minimum Legionellosis risk management requirements for buildings and their associated potable and non-potable water systems.

Establishment by building owners of a program team and (in turn) a water management program for which they are responsible in order to comply with the standard.

Provision of specific and detailed requirements for what Legionellosis control strategies must accomplish and how they are to be documented – but, does not provide (or place restrictions on) what specific strategies are to be used or applied. 

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