Re: Conduit in concrete
watch for low-voltage & communications cables in core line [cast-in-place] installations also. it is important in high-rises and other slab-floor installations to verify that the concrete you are about to core or hammer-drill through does not contain cable. unfortunately once a communications cable is severed in a core line it is often necessary to abandon the cable run and install a new cable, or to enlarge the hole significantly to install a functional splice point. unlike conduit, core line is notoriously difficult to pull through a second time, since it often contains more bends than a similar conduit path. we have had 200-pair telco cable, fiber-optic cable, and other wiring damaged by other trades thusly. never assume that a piece of concrete slab is unencumbered by hidden wiring.