A rating of 29 or 30 DB for hearing protection is something to look for. Cheap safety glasses with a “Z” rating will should be sufficient but better if you like.
I had a pair of industrial ear muffs that would suppress over 85DB but you could hear people talk. Between two large generators at 110 DB you could carry on a normal conversation and even hear the valve train and engine internal noises.
Z-ratings are not ballistic ratings! For goodness sake, spend the money and protect your eyes using APEL glasses or goggles. This is the mil standard:
http://www.peosoldier.army.mil/equipment/eyewear/
I prefer the ESS crossbow, but any are good.