When you’re shuffling the kids onto the big yellow school bus every morning, the last thing you should be thinking about is air pollution. While we trust bus drivers to get our kids safely to school, the diesel-guzzling busses spew toxic tailpipe emissions into the air. And even though some school districts have taken the pollution seriously, and are installing catalytic converters in their vintage fleet of vehicles, these tailpipe controls only help the air pollution levels outside the bus, not inside where children are riding and breathing the air on the way to school. In fact, a new study found that the ratio of pollutants inside the bus cabin can be three to 15 times more emission-heavy than outside city air.
The nasty emissions from diesel engines can cause cancer, asthma and heart disease, and they’re especially a danger to developing young lungs. You would assume that cutting down on school bus emissions outside the bus with new tailpipe controls would do the trick inside the bus, but unfortunately, air pollution is much worse in the cabin. Based on the fact that many of our children hop on the yellow bus twice a day to ride to and from school, this is no laughing matter.
Retrofitting the buses with converters is one step that school districts can take to help protect little lungs. Studies have shown that these converters cut tailpipe exhaust, especially when buses are waiting for kids and idling outside of schools, but the effects on cabin air quality is shakey. Environmental scientists from the University of California, Qunfang Zhang and Yifang Zhu, have conducted tests on air quality within and around school buses, and found that although the converters reduced outside air pollutants by 20- 94%, they had little effect on interior air – the air your kids are breathing on the way to and from school.
What else could schools do? A simple high efficiency particulate air purifier on-board could reduce ultrafine pollutant particles by up to 50% during your child’s ride. The low-cost solution is worthy of suggesting at your next school district meeting.