3M Earplugs Did Not Perform as Advertised
Employees from Aaero tested the earplugs in the year 2000. They stopped the test early because the earplugs weren’t performing well.
In the closed position, they weren’t blocking enough sound. In the open position, they were amplifying all sound rather than diminishing it.
The problem was that the earplugs weren’t fitting right. When worn in the closed position, they were loosening just enough to let in more sound than they should.
The testers conducted a re-test on the closed position. This time, they instructed study subjects to fold the flanges back before inserting the earplug into the ear. By doing this, they achieved the desired fit and adequate noise-reduction scores.
But the company never instructed military personnel to manipulate the earplugs this way. Nor did they do anything to fix the problems with the open position.
Instead, Aearo certified to the government that its earplugs met the requirements for noise reduction and proper handling instructions, even though they did not.
Aearo and later, 3M, sold these defective earplugs to the government for over 12 years. Military service personnel paid the price.