Lost Alpha is a free addon for S.T.A.L.K.E.R. - Shadow of Chernobyl.
be careful! the ceiling is too low in the next room. you might get hurt if you run :D
(my mate's comment on this: yea, its always easier to put a sign somewhere and inform the peeps about some caution, than fix the problem itself... just as in real life :D j/k)
sign was designed by Tzupi, since we didnt find any existing one for this matter :)