§ 3131.08 Firestopping
   (a)   Where the installation of pipes or ducts in walls or partitions requires the removal of any firestopping, the space around the pipes or ducts at the points where firestopping was removed shall be tightly filled with mineral wool or other noncombustible insulating material.
   (b)   Where pipes, ducts, stacks, or fittings pass through a floor construction, all open spaces around them shall be filled with mineral wood, or other incombustible insulating material.
   (c)   Whenever baseboard or wall registers located at the top of supply or return air ducts are installed in stud framed walls or partitions or in construction having concealed interior spaces, an approved firestop shall be installed approximately three (3) inches above such register or grille. In stud framed construction such firestops shall extend the full width and depth of the stud space.