June 5th Thursday 2014

FREEDOM OF SPEECH HOW MANY DECIBELS? SOMETHING TO PONDER?

Sound is measured in Decibels.  Sounds that are 85 dBA or above can permanently damage your ears. The more sound pressure a sound has, the less time it takes to cause damage. For example, a sound at 85 dBA may take as long at 8 hours to cause permanent damage, while a sound at 100 dBA can start damaging hair cells after only 30 minutes of listening.

HOW MANY DECIBELS IS FREEDOM OF SPEECH ALLOWED IN PUBLIC AS MUCH AS THE FOLLOWING (SEE BELOW >>>  

Currently law has decibels capped at 83 decibels for motorcycles built since 1983. So Kenny Price, the man leading Samson Exhaust is now offering a 4″ x 30″ length “Decibel Killer Muffler” with removable baffles and end caps for all Harley.

Jet take-off (at 25 meters)	150	Eardrum rupture
Aircraft carrier deck	140
Military jet aircraft take-off from aircraft carrier with afterburner at 50 ft (130 dB).	130
Thunderclap, chain saw.  Oxygen torch (121 dB).	120	Painful.  32 times as loud as 70 dB.
Steel mill, auto horn at 1 meter.   Turbo-fan aircraft at takeoff power at 200 ft (118 dB).  Riveting machine (110 dB); live rock music (108 - 114 dB).	110	Average human pain threshold.  16 times as loud as 70 dB.
Jet take-off (at 305 meters), use of outboard motor, power lawn mower, motorcycle, farm tractor, jackhammer, garbage truck.   Boeing 707 or DC-8 aircraft at one nautical mile (6080 ft) before landing (106 dB); jet flyover at 1000 feet (103 dB); Bell J-2A helicopter at 100 ft (100 dB).	100	8 times as loud as 70 dB.  Serious damage possible in 8 hr exposure
Boeing 737 or DC-9 aircraft at one nautical mile (6080 ft) before landing (97 dB); power mower (96 dB); motorcycle at 25 ft (90 dB).  Newspaper press (97 dB).	90	4 times as loud as 70 dB.  Likely damage 8 hr exp
Garbage disposal, dishwasher, average factory, freight train (at 15 meters).  Car wash at 20 ft (89 dB); propeller plane flyover at 1000 ft (88 dB); diesel truck 40 mph at 50 ft (84 dB); diesel train at 45 mph at 100 ft (83 dB).  Food blender (88 dB); milling machine (85 dB); garbage disposal (80 dB).	80	2 times as loud as 70 dB.  Possible damage in 8 h exposure.
Passenger car at 65 mph at 25 ft (77 dB); freeway at 50 ft from pavement edge 10 a.m. (76 dB).  Living room music (76 dB); radio or TV-audio, vacuum cleaner (70 dB).	70	Arbitrary base of comparison.  Upper 70s are annoyingly loud to some people.
Conversation in restaurant, office, background music, Air conditioning unit at 100 ft	60	Half as loud as 70 dB.  Fairly quiet
Quiet suburb, conversation at home.   Large electrical transformers at 100 ft	50	One-fourth as loud as 70 dB.
Library, bird calls (44 dB); lowest limit of urban ambient sound	40	One-eighth as loud as 70 dB.
Quiet rural area	30	One-sixteenth as loud as 70 dB.  Very Quiet
Whisper, rustling leaves	20
Breathing	10	Barely audible

Research ,Power Point design , and writing done by  : Don Daniel Johnson Jr.