30 C.F.R. § 57.14104 – Tire repairs.

(a) Before a tire is removed from a vehicle for tire repair, the valve core shall be partially removed to allow for gradual deflation and then removed. During deflation, to the extent possible, persons shall stand outside of the potential trajectory of the lock ring of a multi-piece wheel rim.
(b) To prevent injury from wheel rims during tire inflation, one of the following shall be used:
1. (1) A wheel cage or other restraining device that will constrain all wheel rim components during an explosive separation of a multi-piece wheel rim, or during the sudden release of contained air in a single piece rim wheel; or
2. (2) A stand-off inflation device which permits persons to stand outside of the potential trajectory of wheel components.