How loud is 85 decibels?

Question

I'm considering a home alarm system (ADT) that advertises an interior siren that has a volume of 85 decibels. About how loud is this? Is it enough for security, given that it's an interior (speakers face inward, now outward) alarm?

Thanks!

Answer 1

loud enough not to want to stand next to it without hearing protection.

Answer 2

My Brink's alarm is 90 decibels.  It's pretty d**n loud and high pitch.  I can hear it anywhere in my 2 story house, 2000 sq ft.  It's a sound that I could not sleep through.

I think you are good.  ADT is a well-known alarm company.  There is no reason to question their recommendation.  The installer should be able to make the appropriate recommendations.  The good news is that they can always add or make adjustments after the install.

Answer 3

About the same volume as a room full of people talking, a little less than a lawnmower

Answer 4

Here are some examples of common levels, note though that db is non linear in its reactance and therefore not a simple mater of subtraction or addition to come to a number and will vary in actual loudness based on frequency response.

0 db      Threshold of hearing

30 db    Whisper

40 db     Buzz of mosquito

50 db     Normal conversation

70 db     Vacuum cleaner

100 db   Subway or power mower

120 db   Rock concert

130 db   Jackhammer or machine gun

150 db   Nearby jet plane