Sonic Innovations Inc, Salt Lake City, has performed head-to-head tests with its ion products and those of competitors, and the company says that when placed in a salt fog chamber, ion outperformed four major competitors in resisting moisture.
The testing, conducted at the company’s headquarters using an industry-standard protocol (ASTM Standard B117-03), showed the ion products lasted more than twice as long as the nearest competitor, reports the company.
Michael Nilsson, PhD, VP of auditory research and director of the Center for Amplification and Hearing Research, oversaw the research. Nilsson says that four different, competitive, off-the-shelf hearing aids that have been marketed as moisture resistant and an ion product were tested in the chamber, which is typically used for accelerated environmental testing. The devices were subjected to extreme conditions by being submerged in a distilled water fog containing 5% sodium chloride at a temperature of 95° to simulate heavy perspiration or sweat.
"The products were checked once a day for performance failure," Nilsson says. "One of our competitors’ devices failed when checked at 25 hours, and the other three failed when checked at 42 hours. The ion actually lasted 96 hours before the salt solution caused problems.
"The extended performance in ion was due to several features specifically designed to resist moisture: elastomeric seal to keep sweat out of the battery compartment, hydrophobic membranes to protect the microphones, gold-plated battery contacts, and ports to allow moisture and condensation a path to exit the device," he says.