DECIBELS DESCRIPTION
0 Threshold of normal hearing
10 Normal breathing
20 Mosquito, rustling leaves
30 Whisper
40 Stream, refrigerator humming
50 Quiet office (50-6 0), normal conversation (50-65)
60 Laughter (60-65)
70 Vacuum cleaner, hair dryer, dishwasher (75)
80 Garbage disposal, city traffic noise
85 Diesel truck (84), RV (70-90),
subway, motorcycle (88), lawnmower (85-90)
PROLONGED EXPOSURE TO ANY NOISE OVER
90dB CAN CAUSE GRADUAL HEARING LOSS
100 Train, garbage truck, farm trac
tor (98), newspaper press (97)
NO MORE THAN 15 MINUTES UNPROTECTED
EXPOSURE RECOMMENDED
110 Jet flyover (103dB at 100 ft.),
snowmobile (105), drill/jack
hammer (110), power saw
(110), symphony orchestra (110)
REGULAR EXPOSURE OF MORE THAN 1 MINUTE
RISKS PERMANENT HEARING LOSS
120 Thunderclap (120), stereo
(110-125), discotheque/boom box (120)
140 Rock concerts (110-140), jet
takeoff (130), shotgun firing
(130), boom cars (145)

Test-Result Analysis
Surprisingly, there wasn't a wide margin between the quietest and the noisiest tires for both run-flats and non-run-flats; in fact, the difference was astonishingly small, as these examples illustrate:@ 35 mph -the quietest run-flat tire measured 71dB;the quietest non-run-flat measured 68db;Difference: 3dB

@ 45 mph -
the quietest run-flat tire measured 72dB;the quietest non-run-flat measured 72db;Difference: 0dB

@ 55 mph -
the quietest run-flat tire measured 76dB;the quietest non-run-flat measured 78db;Difference: 2dB

@ 65 mph -
the quietest run-flat tire measured 76dB;the quietest non-run-flat measured 74db;Difference: 2dB

@ 70 mph -
the quietest run-flat tire measured 78dB;the quietest non-run-flat measured 75db;Difference: 3dB

Putting things into a perspective that's easier to relate to, consider this: the total difference between the quietest tire tested at 35 mph (68dB-the Michelin Pilot Sport PS2 non-run-flat) and the loudest tire tested at 70 mph (a 79dB tie between the Goodyear Eagle F1 GS EMT and the Kumho Ecsta MX XRP which are both run-flats) was only 11 decibels-or roughly the sound level of normal human breathing.