Blind door safety

["rtandems@xxxxxxxxx" <rtandems@xxxxxxxxx>]

At work we have much used door between the floor and the offices.  As
it has no window, there are a lot of near collisions.  Adding a window
is not an option.

Does anyone know of a system with a pair of PIRs and simple warning
lights?  Something where a person approaching the door would cause a
light on the other side of the door to go on.  I know I could cobble
together something easily enough, but a commercial solution would be
more likely to be approved.

Thanks,

-Brian