Any driveshaft extending lengthways under the floor of the
passenger compartment of a bus, shall be protected by means of at least one
guard or bracket at that end of the shaft which is provided with a sliding
connection (spline or other such device) to prevent the whipping of the shaft
in the event of failure thereof or of any of its component parts. A shaft
contained within a torque tube shall not require any such device.
[33 FR 19735, Dec. 25, 1968, as amended at 53 FR 49402, Dec. 7,
1988]