You are designing a horizontal distribution system that will have a zone box located 71.6 m (235 ft) away from the telecommunications room (TR). A 50 mm (2 in) conduit is designed from the TR to a…

A count of 2 omits the intermediate pull box required at the 100 ft mark within the first conduit segment before reaching the designed pull box at 120 ft.

BICSI TDMM specifies that pull boxes are required every 30 m (100 ft) in a straight conduit run. In segment 1 (TR to 120 ft via 2-inch conduit), one pull box is required at the 100 ft mark and the designed pull box at 120 ft represents a second pull point - yielding 2 pull points in this segment. In segment 2 (115 ft of 1.5-inch conduit from the pull box to the zone box), one additional pull box is required at the 100 ft mark, and the zone box is excluded per the question - yielding 1 pull point in this segment. The total is 2 plus 1 equals 3.

A count of 4 overcounts the required pull points - no additional pull boxes beyond the 3 identified are mandated by the 30 m (100 ft) spacing rule given the straight-run conduit lengths in this design.

A count of 5 is not supported by the conduit segment distances or the 30 m (100 ft) spacing rule and would represent unnecessary pull points for these straight runs.