A new study has found that the vast majority of American motorists are still washing their cars every time they drive.
Researchers from Duke University found that people wash their cars at least twice a year, with an average of six washing sessions a year.
In contrast, the average American has only had two washing sessions in a year on average.
The researchers compared washing behavior across the country, focusing on wash cycles of vehicles with two people, with the same model year and similar driving habits.
In total, the study examined 2.4 million washing behaviors across four vehicles.
They found that washing a car every time a driver goes to the car wash can be problematic because washing the car can affect odors and emissions.
In a previous study, the researchers found that driving was the most frequent activity people would do when washing their car, with nearly 90% of people washing their vehicles.
Washing in the car after it has been used for longer has been associated with a higher likelihood of getting a water leak, and the authors suggest that washing in the back seat of a car after a long drive is also likely to be associated with high levels of carbon monoxide.
“The average American car owner uses about 2,000 washing cycles per year, and about half of those cycles are washing,” said study author Dr. David L. Bowers.
“While the average person may not be washing in a lot of cars, they are washing in many.”
The study was conducted by researchers from Duke and the University of Maryland, and it was published in the American Journal of Preventive Medicine.
The research is based on data from the National Household Survey on Wash and Odors, a nationally representative household survey.
A key finding of the study was that people who used a washing machine after driving were about twice as likely to get a water-related leak than those who washed their car in a car seat or glove compartment.
“Washing a car is the most common activity people do when they go to the wash,” said lead study author Bowers, who has previously studied water pollution in the U.S. He said the study found that “it may be worth it to wash a car less often if you don’t have to.”
The authors also found that car owners who wash in the rear of the vehicle were more likely to have a water odor problem.
Wiping the car in front of it was associated with an 8% decrease in odors, the authors said.
However, those who wash their vehicles in a glove compartment, in the front, were nearly two times more likely than those in the reverse to get leaks.
The study also found the most popular method of washing a vehicle, the two-person wash, was associated to lower levels of nitrogen oxides, which is linked to a higher risk of heart disease, cancer and other chronic diseases.
In the next study, researchers will focus on washing a second vehicle in the same family.