If I have a normal-speed door (Hexen map format, Doom), and open it, the sound DSDOROPN plays. As expected. When I stand in the door sector, the sounds DSDORCLS and DSDOROPN play, as the door raises back again if I block it.
If the door is opened normal (that is, I am not standing in the way), and close it before the delay is over, DSDORCLS plays (as expected), but when I then again open the door while it is closing, DSDOROPN does not play.