If you're about to work in a room that has a local exhaust ventilation system and a door with an airtight seal,
check BEFORE you shut the door that the fan's not cranked up to its highest setting, or else this will happen:

                        ^^^^ direction of air flow
                        |~ |
                        | ~| <- LEV drawing air through the grate at 70 mph
                        |~ |        and creating a vacuum
         OOOOOOOOOOOOOOO| ~|OOOOOO
         OOOOOOOOOOOOOOO|~ |OOOOOO <- Soundproof working area with 
         OOO you        | ~|   OOO    no way to turn off the LEV from inside
         OOO |          |~ |   OOO
   BLAM \||  v         /~ ~ \  OOO
  BLAM --||\ O        /~ ~ ~ \ OOO
   BLAM /|| \|        ~ ~ ~ ~  OOO
         ||  |       ~ ~ ~ ~ ~ OOO
 door -> ||  |      ~ ~ ~ ~ ~  OOO
         ##~/~\~ ~ ~ ~ ~ ~ ~ ~ OOO
grate -> ##/~ ~\~ ~ ~ ~ ~ ~ ~  OOO
         ##| ~ ~\~ ~ ~ ~ ~ ~ ~ OOO
         OOOOOOOOOOOOOOOOOOOOOOOOO

( The Mock TurtIe ™ --- Thinks you are a cunt, on, Thu 20 May 2010, 19:37, 5 replies)

I'm going to click this partly because you went to the effort of drawing a diagram.

Also for the dangerlols.
(anvil, Thu 20 May 2010, 21:51, closed)

How did you get out?
Or are you still in there?

*click*
(El Fandango carved a big EF onto his nemesis' doublet on .., Thu 20 May 2010, 22:06, closed)

By thumping on the door till someone came along, and displaying the back of my hand,
on which I had written "PLEASE TURN OFF THE LEV, I'M STUCK!"

How I laughed when it was later revealed they never use that LEV anyway, because it fucks up the balances and makes accurate weighing impossible.
( The Mock TurtIe ™ --- Thinks you are a cunt, on, Thu 20 May 2010, 23:44, closed)

I misread this as "about to wank in a room..."
Which made your diagram hilarious as I tried to work it out.
(MJPerry was crude but clickable at, Fri 21 May 2010, 11:48, closed)

My response to this
is the same as when I found out about people being stuck in our -20C room for half an hour at my previous work:

Why the hell isn't there a call button or bell?!
(happy to report that the cold room at my current workplace has a bell)
(xanthine, Sat 22 May 2010, 11:40, closed)