ATLANTA (CBS ATLANTA) — White noise machines designed to help infants sleep can exceed the recommended noise limit and cause damage to a baby’s hearing.
A study released Monday shows that the devices — which play soothing sounds to coax a baby to sleep — are capable of damaging infant hearing as well as impaired development of the child’s language and speech. The commonly-used machines exceeded the decibel limits recommended by hospitals and hearing experts when played at maximum levels.
“These machines are capable of generating hazardous levels of noise. I’m not talking about benign noise — these are capable of delivering noise at industrial levels above that which we would consider safe for industry,” Dr. Blake Papsin of Toronto’s Sick Kids Hospital, and co-author of the study, told CBC News.
The researchers tested 14 unidentified infant sleep machines and played 65 sounds at the maximum volume from various distances to test possible noise damage. All of the machines exceeded the 50-decibel recommended noise limit from both 30 and 100-centimeter distances from a potential infant.
“The infant’s ear … is very different than an adult,” said Papsin. “When we modeled that in the calculations, we found that the estimates of sound pressure that we were using, the safety level might be underrepresented, because the ear canal of the baby actually might be more susceptible than the adult ear. So our safety levels are underestimates.”
When played consistently for eight hours, the sounds registered higher than noise limits set by the National Institute for Occupational Safety and Health for adult workers.
Only one of the tested machines did not exceed the 50-decibel level even from a 200-centimeter distance marker.
“Unless parents are adequately warned of the danger, or the design of the machines by manufacturers is changed to be safer, then the potential for harm exists, and parents need to know about it,” Dr. Gordon B. Hughes, the program director of clinical trials for the National Institute on Deafness and Other Communication Disorders who was not involved in the study, told The New York Times.
Papsin expressed concern that white noise may actually harm an infant’s brain maturity, which is developed when infants hear all sounds.
“Completely removing all informational content at a loud, potentially damaging level is the worst,” he told CBS News.
The study authors caution parents to lower the volume on the noise machines and move them at least 200 centimeters away from an infant in order to prevent hearing damage.