Decibels are a sound mesuring unit. Unlike the decimal system that we use to calculate many things (such as money), the decibel system is different and works more like the Richter scale for earthquakes. The way to calculate can vary but generally, if you are conservative, we might say that everytime the decibels increase by 6, the perception of the sound is doubled. In the decimal system, we usualy figure that an increase from 40 to 52 is a 30% increase (52-40)/40. In the decibel system, it is an increase of 400% (40 to 46 is double and 46 to 52, it doubles again). According to the WHO - World Health Organization, for people to have a good night sleep, the outside noise levels should be limited to 40 db(a). According to our tests, in Montreal, the great majority of car "beeps" are between 60db(a) (8 times the WHO recommendations) and 71 db(a) (32 times the WHO recommendations). Please see the list below where you will find the decibel ratings noted for different makes and models. Please inform yourself on how to deactivate the noisy locking sound emitted by your car for the benefit of everyone (see your car instruction manual or your dealer).