Billy,
The wording and section have changed for the 2006 IRC. (underlining is mine)
- SECTION P2720
- - WHIRLPOOL BATHTUBS
- - - P2720.1 Access to pump. Access shall be provided to circulation pumps in accordance with the fixture manufacturer’s installation instructions. Where the manufacturer’s instructions do not specify the location and minimum size of field fabricated access openings, a 12-inch by 12-inch (304 mm by 304 mm) minimum size opening shall be installed to provide access to the circulation pump. Where pumps are located more than 2 feet (609 mm) from the access opening, an 18-inch by 18-inch (457 mm by 457 mm) minimum size opening shall be installed. A door or panel shall be permitted to close the opening. In all cases, the access opening shall be unobstructed and be of the size necessary to permit the removal and replacement of the circulation pump.