Wear Hearing Protection
Having a wood-shop means noise. Sometimes loud noise. Noise levels can vary widely from machine to machine depending on conditions of use, and machine type. Protecting your ears is super important. One in 10 Americans has a hearing loss that affects his or her ability to understand normal speech. Loss of hearing is most commonly caused by excessive exposure to noise.
What causes hearing loss?
The ear has three main parts: the outer, middle, and inner ear. The outer ear (the part you can see) opens into the ear canal. The eardrum separates the ear canal from the middle ear. Small bones in the middle ear help transfer sound vibrations to the inner ear. Here, the vibrations become nerve impulses, which the brain interprets as music, a hammer hitting wood, a voice, etc,.
When you experience a noise that is too loud, it starts to kill the inner ears nerve endings. Long term exposure to loud noise can destroy these nerve endings. The more nerve endings that die, 
The longer you are exposed to a loud noise, the more damage can occur. The closer you are to the source of noise, the more damaging it can be.
How can I protect myself against hearing damaging noise?
The first and best protection is to wear hearing protectors. You can wear ear plugs or ear muffs. I like the ear muffs because I can stow them on a hook in my shop for easy access and use.