http://brainfireadvice.com/brainmaxx-reviews/

Brainmaxx Just as subtle light sources can prevent deep sleep, noises that do not awaken can disturb sleep. Due to the noisy environments soldiers can be forced attempt and rest in, the Department of Defense has investigated problem. The DOD concluded that white noise played at about 40 decibels was intended for smoothing out the sonic backdrop. Considering that a traditional conversation rates between 60 and 70 decibels, little is much when it comes down to night sounds.

http://brainfireadvice.com/brainmaxx-reviews/