Cooling Tower Basin Sweeping Offers Better Legionnaires Prevention Than Periodic Cleaning

Posted by on Wednesday, September 02, 2015

The recent outbreak o
f Legionnaire's Disease in New York City has proven once again that an ounce of prevention is worth a pound of cure. Legionella bacteria growing in cooling towers was the apparent cause of this outbreak. Once the disease was diagnosed, disinfection and testing immediately became the priority. For prevention, a cooling tower basin sweeping system, along with an effective water treatment program is an effective combination in reducing the risk of Legionella growth.

Rather than manually cleaning the tower basin at regular intervals, or (worse) when problems arise, basin sweeping filtration provides continuous removal of the particulates that provide a habitat to allow Legionella and other bacteria to grow. Cleaner cooling system water also makes water treatment more efficient, requiring less chemical use than a system without filtration. The American Society of Heating and Refrigerating Engineers (ASHRAE) has included cooling tower basin sweeping and centrifugal separators as possible aids in the prevention of Legionella.

ASHRAE Prevention Standards
Guideline 12 in the ASHRAE Handbook points out that..."Keeping the system clean reduces nutrients available for Legionella growth...(and) centrifugal gravity-type separators and bag-type filters can be used to assist in removal of debris.." Fighting Legionella is just one of the advantages of using a centrifugal separator to clean a cooling tower water system.

The newly published ASHRAE Standard 188 (Risk Management for Legionella) requires building owners to document a plan for regular inspections and maintenance of cooling towers. Section 7.2.3 b clearly states that this plan "shall include requirements and schedule for basin or remote sump cleaning." The three largest cooling manufacturers (BAC, Marley, and Evapco) all offer pre-installed basin sweeping piping configurations for their towers for ease of implementation.

The ASHRAE White Paper titled "Benefits of Cooling Water Filtration explains even more benefits of Cooling Water filtration.

Prevention Case Study
Saint John's Hospital in Indiana has heard all the horror stories. Concerned with both the risk of Legionnaires' Disease and employee injury common to manually-cleaning cooling towers, the staff at Saint John's installed continuous filtration cleaning on their cooling tower basins. The LAKOS system also made their water treatment more effective, requiring much less chemical use than before the filtration was installed.  Says their mechanical team leader, "LAKOS basin sweeping is working extremely well. I can't imagine not having it." Download the entire Case Study.

Visit the Legionella Prevention website for more information about how cooling tower basin sweeping can reduce the risk of Legionella and make water treatment more effective.
* Required