Legionella Bacteria

Are you worried about Legionella bacteria in your water system? Legionnaires’ Disease is a potentially fatal disease that can be caused by improperly maintained buildings. Have Indoor Science put together a Legionella risk assessment and water management plan to prevent a problem from ever happening in the first place. You may also consider hiring us to perform Legionella testing as part of the plan. Call (312) 920-9393 to get started.

What is Legionella?

Legionella is a grouping of bacteria that can potentially cause a fatal type of pneumonia called Legionnaires’ Disease. Legionella bacteria prefer slightly warmer water, so it is found in higher concentrations in domestic hot water systems. In general, the larger the building, the greater the risk, but people can contract Legionnaires’ Disease even from homes. Large water systems in hospitals and hotels introduce more risk because the water may be stagnant in rooms that are not often used. The bacteria can thrive in these “dead legs” of pipe and result in an exposure when the faucets are finally turned on.

The greatest concern is when warm, recirculated water gets aerosolized and inhaled by occupants. People with a compromised immune system are particularly at risk for Legionnaires’ Disease.  If you want to learn more, read our blog post on the basics of Legionella.

Water Management Plans

Before doing Legionella testing, we recommend developing a comprehensive Legionella water management plan. An industry standard, ASHRAE 188, should be followed when developing the water management plan. Our owner, Ian Cull, is a member of ASHRAE and has been interviewed on TV regarding Legionella (click picture to view article):

Ian Cull speaking about Legionella testing and water management plans

Legionella Testing

Many clients want to perform Legionella testing for a quick risk assessment prior to the time-consuming process of developing a water management plan.  There are two common methods for performing Legionella sampling.  The first method is culture and is considered the gold standard.  The main advantage is that it only counts viable bacteria which are able to cause disease.  The main disadvantage of culture is the long time to get results.

The second method is called qPCR and stands for quantitative polymerase chain reaction (sometimes referred to as just PCR).  The main advantage of qPCR is that next day results can be obtained.  The main disadvantage is that it cannot distinguish between viable and non-viable bacteria.  In other words, the water treatment system may be doing a great job of killing the bacteria, but the dead bacteria are getting counted in the total.

Often the best approach is to both culture and qPCR testing to get both accurate and quick results.

What does it cost?

The cost of developing a water management plan or doing Legionella testing is based on the size of your building and the complexity of the water system. Call us at (312) 920-9393 and we can put together a plan and price that meets your needs.