Some here are getting this confused with fire rated wall construction. The requirement to seal holes drilled in plates and studs is not limited to fire rated walls. Section R602.8 in the IRC requires fire blocking in various locations. The UBC and IBC have similar requirements. Among other places, the IRC requires fire blocking:

1. In concealed spaces of stud walls and partitions, including furred spaces and parallel rows of studs or staggered studs: as follows:
1.1 Vertically at the ceiling and floor levels.
1.2 Horizontally at invtervals not exceeding 10 feet

In a typical wall, the studs and the top and bottom plates also serve as the required fire blocking. Section R602.8.1.2 Requires that the integrity of all fireblocks shall be maintained. If holes drilled in top or bottom plates would allow fire to pass through, then the integrity of the fire blocking has been compromised. If holes drilled in studs would let fire spread for more than 10 feet horizonally, the same would be true.

[This message has been edited by eprice (edited 08-09-2005).]