(1) All of the components associated with inclined private residence elevators shall be built to a minimum safety factor of 5, unless otherwise specified in this part.

(2) Inclined private residence elevator car frames and platforms shall:

(a) Be built of metal, a combination of metal and wood or other materials of equal strength;

(b) Be suitably prepared and/or protected for exposure to weather.

(3) Incline car chassis shall:

(a) Be built of metal, except for the guiding members; and

(b) Chassis guiding members shall be retained and/or enclosed in guides so that the chassis cannot be derailed.

(4) Cast iron shall not be used in the construction of a car frame or chassis.

(5) A car shall have only one compartment.