1. Hearing and the Ear

2. Ear drum Semicircular canal Hammer, Anvil Stirrup Cochlea Nerve to brain Eustachian tube

3. Loud Sounds & Loss of Hearing The louder and longer you are exposed to a loud sound, the more damage will be done to your hearing. This is known as Noise Induced Loss of Hearing. Damage happens to the microscopic hair cells found inside the cochlea. These cells respond to mechanical sound vibrations by sending an electrical signal to the auditory nerve. Over time, the hairs may get damaged or broken. If enough of them are damaged, hearing loss results.

4. Approx. Decibel Level ExampleMax Exposure 0 Faintest sound heard by human ear. 30 Whisper, quiet library. 60 Normal conversation, sewing machine, typewriter. 90 Lawnmower, shop tools, truck traffic; 8 hours per day 100 Chainsaw, pneumatic drill;2 hours per day 115 Loud rock concert, car horn;15 minutes per day 140 Gun, jet engine; Brief exposure may cause damage. Maximum allowed noise with hearing protectors.

5. 60-70 dBNormal piano practice 70 dBFortissimo singer 3 ft. away 75-85 dBChamber music in small auditorium 84-103 dBViolin 85-111 dBFlute 85-114 dBTrombone 106 dBTimpani & bass drum rolls 120 - 137 dBSymphonic music peak 150 dBRock music peak

6. Other types of damage Loud sounds can also: –burst the ear drum –Damage the nerve endings –Damage the bones of the middle ear –Result in ‘tinnitus’ or ‘ringing in the ear’

7. Sound and Hearing Notes