Dangerous decibels

Today our class went to a programme called dangerous decibels (dB).the lady teaching us was called Toni. We learnt that you can measure sound and that sound is vibrations. She was telling us about how high the decibel level is and if it is 85 then it is safe but anything above 85 decibels then it becomes dangerous. An example of a noise that you can't be around without ear protection is a heavy metal concert and fireworks. The sound off the rain or a washing machine is at 80 db witch is safe and you can  hear it forever.