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Subchapter 7. General Industry Safety Orders
Group 2. Safe Practices and Personal Protection
Article 7. Miscellaneous Safe Practices

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§3326. Servicing Single, Split and Multi-Piece Rims or Wheels.

(a) Scope. This section applies to the servicing of single, split, and multi-piece rims or wheels used on vehicles such as forklifts, industrial tractors, trucks, tractors, trailers, busses, and off-road machines.
Exception: Automobile or light truck tires (Automobile or light truck tires (“LT”) used on light pickups and vans utilizing single piece rims or wheels when a hold-down cone type tire inflation system is used in accordance with the recommendations of the tire manufacturer.
(b) Definitions.
Barrier. A fence, wall or other structure or object placed between a single, split or multi-piece rim or wheel and employee during tire inflation, to contain the rim wheel components in the event of a sudden release of the contained air from the single, split or multi-piece rim or wheel.
Installing a rim wheel. The transfer and attachment of an assembled rim wheel onto a vehicle axle hub. Removing means the opposite of installing.
Mounting a Tire. The assembly or putting together the wheel and tire components to form a rim wheel, including inflation. Demounting means the opposite of mounting a tire.
Multi-piece rim or wheel. A vehicle rim or wheel consisting of two or more parts, one of which is a side or locking ring designed to hold the tire on the rim or wheel by interlocking components when the tire is inflated.
Restraining device. An apparatus such as a cage, rack, or assemblage of bars and other components that will constrain all rim wheel components during an explosive separation of a split rim wheel, multi-piece rim wheel or during the sudden release of the contained air of a single piece rim wheel.
Rim manual. A publication or chart containing instructions, and safety precautions from the manufacturer or other qualified organization for correct mounting and demounting of tires and safety precautions for the type of rim or wheel being serviced.
Rim wheel. An assemblage of tire, tube and liner, where appropriate, and wheel components.
Single piece rim or wheel. A vehicle rim or wheel consisting of one part, designed to hold the tire on the rim or wheel when the tire is inflated.
Split rim (divided) wheel. A vehicle wheel or rim where the inner section and outer section are assembled back to back and secured by bolts and nuts or other fastening devices. The outer section has additional holes that align to the vehicle wheel studs and are secured to the wheel hub with nuts or other approved means of fastening the wheel to the vehicle hub.
Trajectory. Any potential path or route that a rim wheel component may travel during an explosive separation, or the sudden release of the pressurized air. See Appendix A.
(c) Employee Training. The employer shall establish a training program which shall include, as a minimum, the following elements:
(1) The Accident Prevention Program of Section 3203(a).
(2) The employer shall assure that each employee understands, demonstrates and maintains the ability to service single, split and multi-piece rims or wheels safely, including performance of the following tasks:
(A) Demounting of tires (including deflation).
(B) Inspection and identification of the rim wheel components.
(C) Mounting of tire (including inflation with a restraining device or other safeguard required by this section).
(D) Use of other equipment required by this section.
(E) Inflation of the tire when a single piece rim wheel is installed on a vehicle.
(F) An understanding of the necessity of standing outside the trajectory both during inflation of the tire and during inspection of the rim wheel following inflation.
(G) Installation and removal of rim wheels from the vehicle.
(d) Restraining Devices. A safety tire rack, cage, or equivalent protection shall be provided and used when inflating mounted tires installed on single piece, split rim or rims equipped with locking rings or similar devices.
(1) Single piece rims or wheels when installed on the vehicle with the lug nuts fully tightened.
(2) If a tire on a vehicle is under-inflated but has more than 80% of the manufacturer's recommended load chart pressure, the tire may be inflated while the wheel is on the vehicle provided remote control inflation equipment is used, and employees remain outside the trajectory path during the inflation process.
(e) Restraining devices shall comply with the following requirements:
(1) Each restraining device or barrier shall have the capacity to withstand the force that would be transferred to it during rim or wheel separation occurring at 150 percent of the maximum tire specification pressure for the type of rim or wheel being serviced.
(2) Restraining devices and barriers shall be capable of preventing the rim or wheel components from being thrown outside or beyond the device or barrier for any rim or wheel positioned within or behind the device.
(f) Care and Maintenance of Restraining Devices.
(1) Restraining devices and barriers shall be visually inspected prior to each day's use and after any separation of the rim wheel components. Any restraining device or barrier exhibiting damage such as the following defects shall be immediately removed from service:
(A) Cracks at welds;
(B) Cracked or broken components;
(C) Bent or sprung components caused by mishandling, abuses, tire explosion or rim wheel separation;
(D) Pitting of components due to corrosion;
(E) Restraining devices or barriers requiring structural repair such as component replacement or rewelding shall be removed from service until they are repaired by either the manufacturer or a California certified welder in accordance with Section 3326(e).
(g) Wheel Servicing and Mounting.
(1) There shall be available in the service area a current split and multi-piece Rim or Wheel Matching Chart, a Typical Rim Contours & Marking Location Chart, and current Rim Manual containing instructions for the proper tools recommended for the type of rim or wheel being serviced.
Note: Other publications providing at least the same instructions, safety precautions and other information contained in the charts may be used provided the publications are readily available for reference by employees.
(2) The employer shall furnish and assure that only tools recommended in the rim manual for the type of rims or wheels being serviced are used.
(3) Single, split and multi-piece rim or wheel components shall be inspected prior to assembly. Any rim or wheel or rim or wheel component which has been rendered unfit by being bent out of shape, pitted from corrosion, broken, or cracked shall not be used and shall be marked or tagged unserviceable and removed from the service area. Damaged or leaky valves shall be replaced.
(4) Before making any repairs or welds on rims or wheels, the tire shall be removed and remain off the rim or wheel until the repair is complete and any welds have returned to ambient temperature. Any repair involving welding on the rim or wheel or any of its components shall only be done in accordance with the manufacturer's specifications.
(h) Demounting Tires.
(1) Split and multi-piece rim tires shall be completely deflated by removing the valve core. A wire or equivalent device shall be inserted into the center of the valve stem to ensure no obstruction exists that would prevent complete deflation, before removal of the wheel from the axle.
Note: This does not apply to tires on rim wheel assemblies with no obvious or suspected damage to any rim wheel components or the tire.
(2) No heat shall be applied to a single, split or multi-piece wheel or wheel component except that frozen or broken lug nuts may be cut off after the tire is completely deflated.
Note: Subjecting wheels to excessive heat may result in structural deficiencies. Therefore, care shall be exercised while cutting off lug nuts to avoid excessive heating of the wheel. Wheels subjected to prolonged heating shall be removed from service.
(3) Tires shall be completely deflated by removal of the valve core before demounting.
(i) Mounting Tires and Inflation.
(1) Mounting and demounting of the tire:
(A) Shall be done only from the narrow ledge side of the wheel.
(B) Care shall be taken to avoid damaging the tire beads while mounting tires on wheels.
(C) Tires shall be mounted only on compatible wheels of matching bead diameter and width.
(2) Rim flanges, rim gutters, rings, bead seating surfaces and the bead areas of tire shall be free of any dirt, surface rust, scale or loose or flaked rubber build-up prior to mounting and inflation.
(3) Wheel component acceptability. Multi-piece wheel components shall not be interchanged except as provided in the charts or in the applicable rim manual.
(4) Prior to assembly the size (bead diameter and tire and/or wheel widths) and type of both the tire and wheel shall be checked and incompatible parts shall not be assembled.
(5) Non-flammable rubber lubricant shall be applied to bead and rim mating surfaces before assembly of the rim or wheel unless the tire or wheel manufacturer recommends against it.
(6) Tires shall be inflated in accordance with Section 3325.
(7) If a bead expander is used, it shall be removed before the valve core is installed and as soon as the rim or wheel becomes airtight (the tire bead slips onto the bead seat).
(8) Employees shall be instructed not to take a position over the tire during inflation and to remain outside the trajectory.
(9) Except as permitted in Section 3326(i)(10), tires shall not be inflated when any flat, solid surface is in the trajectory and within one foot of the sidewall.
(10) Tires may be inflated outside a restraining device to a pressure that shall not exceed 5 pounds per square inch (psi) to force the tire bead onto the rim ledge and create an airtight seal and/or to assist the seating of the lock rings.
Exception: Where higher pressures are recommended by the tire manufacturer.
(11) Whenever a single, split or multi-piece rim wheel is in a restraining device, employees shall be instructed not to rest or lean any part of their body or equipment on or against the restraining device.
(12) Except during the operation described in Section 3326(i)(10) employees shall be instructed not to attempt to correct the seating of side and lock rings by hammering, striking, or forcing the components while the tire is pressurized.
(13) After tire inflation, the tire and rim or wheel components shall be inspected before removal from the restraining device to ensure that they are properly seated and locked. If further adjustment is necessary, the tire shall be deflated by removal of the valve core before the adjustment is made.

Appendix A

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