Leaf blowers should have a much more limited decibel range (and that is a legal action that can be taken). You note that all users are wearing sound proof ear protectors. Unfortunately, the student walking home from school or the passenger waiting for a bus, or just kids playing in their own homes or yards have no such protection. In much of Europe during WWII, people were required to have their gas masks with them at all times. Will the constant leaf blower noise soon require us all to carry ear protectors?