Wood-working tools can be very loud. Noise levels of 104 - 110 dB [have been measured in real-world use](http://www.woodworkingtips.com/etips/etip43.html). (Theoretically, the noise levels are supposed to be measured one meter away from the source of the noise. One meter is 3' 3 3/8".)

There are a few forms of hearing protection available. For example:

* Squishy ear-plugs for putting in one's ear canals. [Typical earplugs](http://www.rockler.com/disposable-ear-plugs) are rated for about 32 dB of noise reduction.
* Headset-like earmuffs. [Typical earmuffs](http://www.rockler.com/vibe-29-earmuff-hearing-protectors) are rated for about 29 dB of noise protection.

Is it considered best practice to wear both ear-plugs and earmuffs when working with power tools? Or does the [combined noise reduction](http://www.noisehelp.com/double-hearing-protection.html) make it so hard to hear non-tool noise that you will not hear other potential dangers?