Skip to content
Home » How to reduce Legionella risk in five simple steps

How to reduce Legionella risk in five simple steps

Over six thousand cases of Legionnaires’ diseases are reported every year. This is according to information released by the Centers for Disease Control and Prevention.

Even if nine out of ten Legionnaires’ disease cases are actually preventable. Older workers and individuals with compromised immune systems are still being diagnosed every year, according to the Centers for Disease Control and Prevention.

As the number of cases continues to increase, companies should have effective testing and water management plans (also known as WMP). These plans should be in place to prevent outbreaks of Legionella. Legionella is the bacteria that causes Legionnaires’ disease, from spreading through water supplies.

To reduce the real risk of an outbreak in a facility, five steps should be taken to make sure workers and the community are safe from the respiratory illness.

Step 1: Validate Your Water Management Plan

With ANSI/ASHRAE Standard 188-2015, water management programs are an industry standard for large buildings and offices in the United States. Large facility water supplies can be complex and harbour multiple pathogens. Maintenance, service interruptions and renovations may cause even more hazardous conditions. Routine tests for Legionella pneumophila is the best way to determine if a water management plan (WMP) is actually working.

Step 2: Test for Legionella pneumophila

One single species of Legionella bacteria, the Legionella pneumophila is the main cause of Legionnaires’ disease. The species is behind 99% of the outbreaks monitored by the regulatory organisms. Accordingly, Veterans Administration healthcare organisations are required to test for Legionella pneumophila every 3 months.

World Health Organisation advisors recommend testing for Legionella pneumophila, “not Legionella species specifically. Since this genus may contain many species that don’t cause the illness”.

Step 3: Rely on a Culture Test

Rapid tests, like the polymerase chain reaction tests, may offer quicker results in an outbreak context. But culture tests are the true reliable source of an accurate quantification for Legionella. PCR and direct fluorescent antibody tests don’t discriminate between Legionella and controlled bacteria.

Step 4: Ensure Results are Reproducible And Accurate

Routine testing for Legionella pneumophila is the best and only way to guarantee the water management plan (WMP) is truly effective. Apart from identifying the presence of L. pneumophila in the system, you will need consistent data about the quantity and locations of the bacteria to respond adequately. Safety responsible stakeholders must have consistent data to make the right decisions about potential water quality issues.

Step 5: Choose an Accredited Laboratory for Testing

ANSI/ASHRAE Standard 188-2015 requires the responsible personnel using “a laboratory with proven proficiency in the subject method, such as evidenced by certification by a national or local government agency”. Labs that can perform a Legionella risk assessment form and test with methods that are part of their accreditation and quality system demonstrate that their tests are performed at the highest level of quality. Accreditation affords the best legal coverage if testing results ever come under question.

In order to reduce the real risk of a Legionella outbreak in a facility, the above five steps should be taken to make sure workers and the community are safe from the respiratory illness.