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FIRE SERVICE AND GENERAL FIRE SAFETY TOPICS => Technical Advice => Topic started by: Allen Higginson on March 11, 2006, 02:17:56 AM

Title: Reduction of dB levels over distance
Post by: Allen Higginson on March 11, 2006, 02:17:56 AM

Quick one - typically,does the dB levels drop by 6 dB every 2 metres or does it decrease by 6 dB with every "double" (ie - 1,2,4,8,16...etc.)?Had a bit of a brain stormer and haven't my references handy.
Cheers in advance

Title: Reduction of dB levels over distance
Post by: Graeme on March 11, 2006, 09:32:04 AM

It drops 6 dba every time the distance from the sounder doubles.

2-6
3-9.2
4-12
5-13.9
6-15.5
7-16.9
8-18 etc

Title: Reduction of dB levels over distance
Post by: Allen Higginson on March 11, 2006, 08:45:35 PM

Ta to the Senior Member from the one having the Senior moment - that must be a keg I owe you by now!

Title: Reduction of dB levels over distance
Post by: Graeme on March 12, 2006, 10:46:03 AM

No worries