Pardon me while I trip over this pipe and impale myself...

This is a good example of where NOT to have a fire sprinkler pipe installed: Running right across the floor of a walk-on wire tension grid. Not only is it a huge trip hazard, but the hold-down calmps they used were left with bolt ends sticking up far enough to impale someone. Clearly, the bolts should be trimmed-off and the pipe maked with a bright yellow / black OSHA hazard marking tape.

Poor coordination in the design and installation phases cause things like this to happen. In reviewing the site, it was obvious that the sprinkler contractor just took the easy way through, as there was plenty of room overhead to run the pipes above even the tallest person working on the grid.

Not seen in the picture: right above the pipes were 2'x4' fluorescent work-lights that were suspended with the bottoms at about 5-8" above the grid deck. So, while you were busy looking down to keep from tripping, you hit your head on the sharp metal corners of the light fixtures (painted black to hide them). Yet another good reason to wear a hard-hat in the theatre!