Still not sure what it is.

I know I do a test at work where I put in a 3 KHz deviated, 1 KHz tone
into the FM receiver
port while probing an audio point going to the SINAD port on the test
equipment.
Increasing the input level makes for a larger SINAD value (which makes
sense)
Looking for at least 12 dB SINAD.
What is so special about 12?

Can't get my mind around it. Is the test tone 12 dB stronger than noise
+ distortion?

Is the the input value in dBm on the test equipment the sensitivity of
the receiver at 12 dB SINAD.
The 'at 12 dB SINAD' still gets me.