Data and Drawings
From here, you can view & download useful acoustic reference and sample drawings.
A Scale Reading
When it is desired to convert a set of octave band Sound Pressure Levels into an equivalent A scale reading, apply the following corrections to the octave band SPL values.
Decibel Levels of Some Common Sounds
Typical sound pressure levels (dBA) of some common sounds.
Addition of Decibels
Decibels are logrithmic values and cannot be added by normal algebraic addition. The following is a simple method for adding decibels.