Sound level

What is an average db rating of say a 30-06 at the muzzle? No suppression. What is highest acceptable level of db's that is considered safe?

.30-06 in 24" barrel 158.5dB. In 18" barrel 163.2dB.
"Safe" depends on exposure time. You can safely handle 127 dB for 1 second total within 24 hours. 140 dB causes immediate nerve damage.
http://www.noisehelp.com/noise-dose.html

The Silencer Shop has videos that perform before and after tests. Most of them aren't terribly interesting, as the performance of most suppressors of similar size is very equivalent, but the before on .308s appears to be mid 160s and the after appears to be high 130s. The 223s are about 10db lower at both ends. This is with un-braked rifles.

Thanks, guys this is just what I was looking for!

It is safe to assume any unsuppressed 30.06 configuration can cause immediate, permanent hearing damage with one shot.
Suppressed, it is still wise to wear hearing protection.

In the construction business any time spent in a noisy situation 86 db and above is required hearing protection. That equals a moderate speech. I turn the radio up just a little past half way and it was registering past 86.

you all are going to have to speak up, after being in a 5" gun mount at general quarters and working around construction equipment for 37yrs, I can hardly hear you.

So this would justify donning a pair of muffs when the better half begins speaking, right?