I ' ve wondered about this . I assumed they would force air flow like in any tunnel and install filters so the particles would not go out of the tunnel . Haven ' t card enough to verify any of that so far . <| sep |> ahh cool then <| sep |> join my club guys , IFC SS , or add me pdpfakasSmart build up , not rushing the computer . i am RW , and i have a striker and a CM . You are both welcome <| sep |> HDI HDI adjusted for inequality <| sep |> My westie is also 14 ! How is your dog ' s skin ? Mine has a bit of problem with a chronic dermatitis . <| sep |> I do believe that , at the end of the day , NASA ' s priorities and their budget should be on deep space explorationThey are . You need a launch pad to get to Mars and beyond , and Earth is the only one that we ' ve got .