K-12 Relief Funds: School Bus Ventilation Systems

Shortly before leaving office, President Donald Trump signed the Consolidated Appropriations Act of 2021 into law. Part of this law includes over $54 billion in funding grants to help both public and charter schools respond to the COVID-19 outbreak.

The bill already mentioned possible uses for the grants, such as purchasing PPE or barrier systems to put into buses. One open question was whether school bus ventilation systems would also be covered by these grants. School Transportation News emailed the Department of Education directly to ask, and the answer they got back was a clear "yes."

So, if your district is looking at bus upgrades to improve COVID-19 safety, ventilation systems are on the menu. But are they worth the effort of installing?

The Case For School Bus Ventilation Systems

There are two primary ways that COVID-19 can spread - through the air or through common contact with physical objects. The former is far more likely to occur than the latter, with around 90% of transmission believed to occur via exhaled microdroplets of water in the air.  

So, on the face of it, ventilation systems could potentially do a lot of good!

The majority of these systems work through positive continuous air pressure. In other words, they work a bit like breathing. They take in air from outside the bus, forcing it into the interior, and forcing internal air out as a result. The biggest benefit here is that it prevents the air within a bus from becoming stagnant, or saturated with infectious agents.

Also, these ventilation systems almost always include filters, which further help prevent disease spread. Viruses adhere to any surface they touch, so they are relatively easy to capture on properly designed filters.

While we can find no objective scientific studies into the effectiveness of such ventilation systems, there seems very little reason to think they aren't effective.  Installing ventilation would almost certainly reduce the risk of viral contamination onboard buses.

One possible counterargument is "why can't we just open the bus windows?" And yes, that is an option, but it has two big drawbacks. First, having numerous windows open will make the ride windy and noisy, significantly reducing rider comfort. Also, open windows will cause substantial wind drag, reducing your buses' gas mileage by a large amount. Given how poor the MPG on most buses can be, this seems like a sub-optimal solution - although it is inexpensive in the short term.

School bus ventilation systems have the potential to increase rider safety, without compromising bus performance. If the government is willing to fund their installation, in our view, that makes them a viable new option in fighting COVID-19.

Has your district looked into the viability of school bus ventilation systems? If so, please share your findings in the comments!