One can hear 120 dB for a duration of [[1]]. 

The maximum allowable noise level is 120 dB for 30 seconds. There is a high risk of hearing loss and other mental health problems if someone hears for longer than this period of time.

The effective distance of a 100 dB sound in a very noisy environment is 1.8m, and the distance for a 120 dB sound is approx 18m (10 times the distance).