A recent study examining the loudness of automated hand dryers in public places published in Paediatrics & Child Health suggests that many hand dryers operate at levels far louder than their manufacturers claim.

Noise greater than 100 dBA – the maximum allowable noise level for products/toys meant for children – is considered dangerous to children’s hearing.

The study’s author, Nora Louise Keegan, designed the study to find out how loud hand dryers are in real-life scenarios at children’s and adult ear heights.

“Sometimes after using hand dryers my ears would start ringing,” 13-year-old Nora Keegan from Calgary, Alta., told NPR. “I also noticed that children would not want to use hand dryers, and they’d be covering their ears.”

Forty-four hand dryers in public washrooms in Alberta were each measured for peak sound levels in a standardized fashion. Each dryer was measured at 10 different combinations of heights and distances from the wall, and with and without hands in the air stream coming from the hand dryer, for a total of 20 measurements per dryer.

Keegan discovered that older-looking (and slower air-flow) dryers were usually quieter than newer dryers which appeared to have high airflow. She also noted Xlerator (Excel) and two models of Dyson Airblade hand dryers were far louder than what the companies claimed and always exceeded established Canadian maximum allowable noise levels for children’s toys.

The author suggests the results can be used to guide regulators, builders, and landlords in making decisions about which dryers to install in public facilities.