I'm sure it was some sort of oversight on my part, but I was invited to shoot at the Pit with a friend. When the gal in the little office heard/saw that I was shooting my AR with a suppressor, she about had a cow and sternly asked for me to prove I was legally allowed to own the can. I carry documentation and after seeing it she was fine. Not sure what that was all about. I am an Oregon resident and maybe I was (probably) ignorant to the law/rules of shooting in Wa. with a can.
For many years we in Washington were allowed to own suppressors - but they were illegal to use! Go figure. Anyways, that law was changed about a year and a half or so ago (I forget the exact date). We went through a transition period while we were trying to figure out how to behave. At first we felt the need to ensure that anyone bringing one had their paperwork (call it due diligence). Later we decided why should we be a nanny? If someone brings and uses their suppressor without the proper paperwork and they get questioned by law enforcement, its really has no impact on the range. So now, suppressors are the quietest things on the range!
We do have limitations in that we DO NOT allow the use of homemade suppressors. You know the kind. The ones made out of oil filters, soda bottles, etc.