With cats I have found that the only thing that is safe to use is a swab (AKA mop). They can hang on but not climb. They will tear the hell out of your arm if you try to grab them. Dogs are a different story, there is little to grab and they can also tear the hell out of your arm. Of course they are in full panic and "trying" to help.For our dogs we have always kept them in a wide strap harness with a heavy leash attached. They also wear a life jacket. The leash generally keeps them onboard and serves to lift them back when the inevitable happens. We normally cruise with our Husky so we are used to good sized dogs.