Under Pressure: Holiday Breaks Prove a Good Time to Check Tires
Without realizing it, most students are arriving to school with less than the recommended amount of pressure — tire pressure, that is. According to a 2007 survey by the Rubber Manufacturers Association, 85 percent of drivers fail to properly check tire pressure, but some schools have been working to change that.
One of the first universities to address the impacts of improperly inflated tires was Carnegie Mellon University (CMU) in Pennsylvania, which received a lot of attention in 2005 over an informal, one-day student tire pressure study on campus. “When you’re the first one out of the box, like we were on that, you make a lot of ‘boo boos,'” admits Deborah Lange, executive director of CMU’s Steinbrenner Institute.
During Earth Week, eight CMU students used digital tire gauges to measure the air pressure in the tires of 81 cars parked in a campus garage. They found that only one car had the proper air pressure in all four tires, based on the suggested maximum air pressure stated on the tires’ sidewalls. The study concluded that based on the 3,000 parking permits CMU issues to its students, the campus community could save more than $1,296,000 annually in fuel efficiency costs through proper tire inflation.
The U.S. Department of Energy and the EPA claim that drivers can improve their gas mileage by 3.3 percent by having properly inflated tires, and in an average car, that saves about two gallons of fuel and prevents over 40 pounds of CO2 emissions every month.
CMU was heavily criticized for its study, over everything from exaggerated savings estimates to how data was gathered. “It wasn’t a rigorous research study,” explains Lange. “Part of it was just the effort itself to raise awareness in people and not so much on what were the absolute numbers we calculated as being a savings in CO2 emissions.”
The positive side of CMU’s study, however, also spread around the country and was heard by students and faculty at Furman University in South Carolina. “We learned from them,” says Dr. Bill Ranson, professor of Earth and Environmental Sciences at Furman. Students held their first tire pressure check right before Thanksgiving break in 2006, about 18 months after CMU’s study. Furman volunteers have since conducted free tire pressure checks for students before every Thanksgiving break and at the end of each Spring term.
Over the years, volunteers have serviced over 500 vehicles and estimate saving over 1,200 gallons of fuel, $3,000 in fuel efficiency costs and 25,000 pounds of CO2. Drivers are directed to an impromptu “drive-thru” service area where volunteers check and fill tires accordingly, record the data and hand out brochures on car maintenance and safety.
“It’s really simple,” says Reece Lyerly, the current student organizer for Furman’s tire pressure checks. “It’s what I like about the checks. We get people asking if we could do this every month.”
When knowing how much to adjust a tire’s pressure, Furman volunteers refer to the recommendation specific for that vehicle, which is usually found on a placard inside one of the car’s doors. This recommendation typically suggests a lower psi (pound per square inch) than listed on the tires’ sidewalls (the maximum psi listed on tires is for a vehicle carrying a maximum load on those tires).
Tires can be over or under-inflated by 20 percent without a driver being able to tell visually, and tires naturally lose about one to two psi a month. It’s always best to check a tire’s pressure when it is “cold,” which means it has been stationary for at least three hours or driven less than 1.25 miles. Since students park their cars for most of the day while in class, and some may not have driven far to get to campus, universities lend themselves well for these tire pressure checks.
Moreover, these events do not cost much, are run primarily on volunteer efforts, offer something with which drivers can easily identify — saving money — and most drivers don’t even have to get out of their cars. “Furman is not always the easiest place to have environmental stuff going on,” adds Lyerly, “and so to see this event be accepted so well by the student body is really cool.”