Humidification: A hands-off way to reduce the of COVID-19 in schools

While wearing masks, hand washing, social distancing, and disinfecting are effective ways to reduce the spread of COVID-19, each of these measures take a concerted focus on the part of the building occupants. As we navigate the COVID-19 pandemic, it’s a smart idea to look for hands-off approaches to mitigate the transmission of viruses. The addition of humidification to keep the indoor relative humidity within a healthy range is not only safe, but easy and efficient because it requires no extra thought or effort.

The costs are important to consider too. Consumable items like hand sanitizer, soap, masks, and disinfectants all cost money and will be used up. In contrast, a commercial humidification system can last for over 20 years while providing broad protection for building occupants against viruses like COVID-19, Influenza A, Severe Acute Respiratory Syndrome (SARS), Middle East Respiratory Syndrome (MERS), and others.

The indoor relative humidity (RH) level, or the amount of water vapor present in air, should be kept between 40 and 60% RH to reduce the transmission of COVID-19 and other viruses. The RH level in a school building can vary greatly depending on climate, forced-air heating, mechanical cooling, and many other factors. An inexpensive hygrometer can be used to test and monitor RH levels in a classroom.

Researchers at the Mayo Clinic in Rochester, Minnesota, investigated how indoor humidity levels affect transmission of respiratory viruses in a classroom setting in a recent study.

This study showed that rooms with commercial-sized humidifiers had:

  • Significant decrease in the percent of total air samples containing influenza A.
  • A trend toward a decreased percent of surface samples containing influenza A.
  • Samples with influenza A contained fewer “live” viruses and were therefore less infectious.
  • Fewer flu-like illnesses reported.

DriSteem makes it easy to design a humidification system that is just right for your application. These easy to use calculators and selection tools will help you get there quickly and easily.


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allows you to make a quick calculation of the humidification load for your application.

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