Seismic Airgun Testing Survey
As you may have heard there is proposed seismic air gun testing in our waters for offshore drilling in Delaware. This testing will be twice the decibel level of a jet engine. According to the Bureau of Ocean Energy Management (BOEM) … “These airguns generate air bubbles that expand and contract in the water column, and the resultant noise levels are generally in the 225-260 decibel range for airgun arrays “ The human ear drum can rupture at 150 decibels, which can occur if you stand 25 meters from a jet engine at takeoff. The loudest sound possible in air is 194 decibels, but in water that can be greatly amplified. Below is a chart from Purdue University with possible results from being exposed to different decibel levels. It has been proven that seismic testing not only disrupts fisheries but also is detrimental to marine life, especially mammals. We put together a quick survey to see what people think of the idea of seismic testing in the Atlantic Ocean.
Below is a chart from Purdue University with possible results from being exposed to different decibel levels.
|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).||
|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|
Here are some interesting numbers, collected from a variety of sources, that help one to understand the volume levels of various sources and how they can affect our hearing.
|Weakest sound heard||0dB|
|Whisper Quiet Library at 6′||30dB|
|Normal conversation at 3′||60-65dB|
|Telephone dial tone||80dB|
|City Traffic (inside car)||85dB|
|Train whistle at 500′, Truck Traffic||90dB|
|Jackhammer at 50′||95dB|
|Subway train at 200′||95dB|
|Level at which sustained exposure may result in hearing loss||90 – 95dB|
|Power mower at 3′||107dB|
|Power saw at 3′||110dB|
|Sandblasting, Loud Rock Concert||115dB|
|Pneumatic riveter at 4′||125dB|
|Even short term exposure can cause permanent damage – Loudest recommended exposure WITHhearing protection||140dB|
|Jet engine at 100′||140dB|
|12 Gauge Shotgun Blast||165dB|
|Death of hearing tissue||180dB|
|Loudest sound possible||194dB|
|OSHA Daily Permissible Noise Level Exposure|
|Hours per day||Sound level|
|.25 or less||115dB|
|NIOSH Daily Permissible Noise Level Exposure|
|Hours per day||Sound level|
|.25 or less||100dBA|
|Perceptions of Increases in Decibel Level|
|Barely Perceptible Change||3dB|
|Clearly Noticeable Change||5dB|
|About Twice as Loud||10dB|
|About Four Times as Loud||20dB|
|Sound Levels of Music|
|Normal piano practice||60 -70dB|
|Fortissimo Singer, 3′||70dB|
|Chamber music, small auditorium||75 – 85dB|
|Piano Fortissimo||84 – 103dB|
|Violin||82 – 92dB|
|Clarinet||85 – 114dB|
|French horn||90 – 106dB|
|Trombone||85 – 114dB|
|Tympani & bass drum||106dB|
|Walkman on 5/10||94dB|
|Symphonic music peak||120 – 137dB|
|Amplifier, rock, 4-6′||120dB|
|Rock music peak||150dB|
- One-third of the total power of a 75-piece orchestra comes from the bass drum.
- High frequency sounds of 2-4,000 Hz are the most damaging. The uppermost octave of the piccolo is 2,048-4,096 Hz.
- Aging causes gradual hearing loss, mostly in the high frequencies.
- Speech reception is not seriously impaired until there is about 30 dB loss; by that time severe damage may have occurred.
- Hypertension and various psychological difficulties can be related to noise exposure.
- The incidence of hearing loss in classical musicians has been estimated at 4-43%, in rock musicians 13-30%.
- Recent NIOSH studies of sound levels from weapons fires have shown that they may range from a low of 144 dB SPL for small caliber weapons such as a 0.22 caliber rifle to as high as a 172 dB SPL for a 0.357 caliber revolver. Double ear protection is recommended for shooters, combining soft, insertable ear plugs and external ear muffs.
Statistics for the Decibel (Loudness) Comparison Chart were taken from a study by Marshall Chasin , M.Sc., Aud(C), FAAA, Centre for Human Performance & Health, Ontario, Canada. There were some conflicting readings and, in many cases, authors did not specify at what distance the readings were taken or what the musician was actually playing. In general, when there were several readings, the higher one was chosen.
The National Institute for Occupational Safety and Health (NIOSH) -http://www.cdc.gov/niosh/topics/noise/
American Tinnitus Association – Information and help for those with tinnitus
Hear Tomorrow – The Hearing Conservation Workshop
H.E.A.R. – Hearing Education and Awareness for Rockers
American Tinnitus Association – for musicians and music lovers
Turn It to the Left – from the American Academy of Audiology
Listen to Your Buds – from the American Speech-Language-Hearing Association
Binge Listening: Is exposure to leisure noise causing hearing loss in young Australians? [pdf] – report from Australian Hearing, National Acoustic Laboratories
Hearing Aids and Music: Interview with Marshall Chasin, AuD – from the American Academy of Audiology
Safe Listening Resources – from the National Hearing Conservation Association
TOTAL RESPONSES = 296
Do you feel that seismic testing is necessary in the Atlantic Ocean?