CH-37 Mojave Helicopter decibels
Although that specific information may be impossible to get without starting up a Mojave and standing underneath with a sound level meter, it is generally understood that helicopter noise can easily exceed 100db. The CDC indicates that permanent hearing loss can occur after 15 minutes of exposure to this level of sound.
Here is a link to a study on helicopter decibel levels.
Here is a link to the CDC page on hearing loss.
Here is a link to a Purdue University chart, listing a Bell helicopter’s sound level at 100db flying 100 feet overhead.
I hope this helps at the VA. Thank you for your service.