Managing Installations in Data Centers : the Hidden Risk of Legionella

In 2021, a standard Google datacenter consumed approximately 1 700 000 liters of water and in 2022, this number increased by 20%. However, these titanic servers hide more challenges than environmental ones like facility management issues, some with serious healthcare implications. One often overlooked is the alarming affinity the pathogenic bacteria Legionella pneumophila has with datacenters' cooling systems where all factors enable it to thrive.

How the cooling systems became high risk Legionella nests

Data centers generate massive amounts of heat and must be cooled down to avoid meltdown and data loss. For that, most companies such as Google chose water-based cooling systems.

According to Urs Hölzle’s 11/22/22 official google publication, these cooling systems reduce the overall energy consumption of Datacenters by 10%.

However, the water consumption is equally massive, Google’s data centers next to Council Bluffs, Iowa, needs 3 billion liters per year.

For Legionella pneumophila, the bacteria responsible for more than 98% of human legionnaire disease contamination, which thrive in water between 20 to 45°C, these cooling systems are a perfect fit.

The Legionnaire disease, a form of pneumonia, can be fatal in about 10% of cases.  In case of contamination, all data center employees are exposed to this sanitary risk. Because Legionella pneumophila spreads to humans through contaminated water droplets in the air (produced by cooling towers expeling steam out of the system), local populations will also be impacted up to several kilometers.

Three steps to limit the risk all data center should follow

With such high stakes, it is essential to limit the risk as much as possible. Fortunately, Legionella pneumophila control is a well-documented issue and can be summed up to three key points:

1. Quality heat control: Legionella pneumophila will die in a few hours at 60°C or higher. Water-cooling systems are so efficient they can make temperature drop 10°C by absorbing the heat and diffusing it through the water in the system. Thorough tests must be conducted to ensure the temperature does not drop too low. Legionella pneumophila often nests in piping dead-leg, abandoned or hard to access, be sure to consider the entirety of the infrastructure.
2. Regular microbial testing: Performing only one mandatory analysis a month is not enough to control efficiently this sanitary risk. Indeed, when Legionella pneumophila starts to colonize a pipe, it takes less than a few days to reach the threshold that makes it at risk for humans. Solutions to ensure water quality control exist, either with microbiological contract laboratories or with on-site equipment and should be carried out before mandatory testing to ensure safe results. Diamidex offers different solutions depending on your needs for the rapid detection of Legionella pneumophila, with both equipment and kits.
3. Quick chemical answer to contamination: In case of detected contamination, the use of biocides becomes necessary. But their high environmental impact and their important costs compared to preventive monitoring makes them a last resort solution. Some industries use them to control the quality of water without any test, and we should strive to limit their use as much as possible.

If these steps are observed in data centers, the risk for Legionella pneumophila contamination should be close to zero. Applied alongside standard security regulation, they should be an essential part for any safe workplace, not only for datacenters. Diamidex’s mission is to raise awareness about the risks these systems present and to provide easy to implement solutions to professionnals until only Legionella-free datacenters exist.