Cal. Code Regs. tit. 8, § 504
(a) Transportation tanks mounted on truck or trailer frames shall be placed on saddles or bolsters with the center of gravity as low as possible. Such saddles, bolsters, and/or other fastenings shall be designed to withstand a loading in any direction equal to the loaded weight of the tank when filled to the maximum permissible level with a factor of safety of at least 8. Transportation tanks of the so-called “frameless-type” shall not be used in anhydrous ammonia service until the design of the tank and tank supports has been submitted to the Division and found acceptable. The installation must also comply with DOT requirements.
All transportation trailers shall be firmly and securely attached to the vehicle drawing them by means of suitable drawbars supplemented by a safety chain (or chains) or safety cables.
Every transportation trailer or semitrailer shall have a reliable system of brakes, and adequate provision shall be made to operate the brakes from the driver's seat.
Every transportation trailer shall be equipped with self-energizing brakes.
Transportation trailers shall be so designed that the towed vehicle will follow substantially in the path of the towing vehicle and will not whip or swerve dangerously from side to side.
Where a fifth wheel is employed, it shall be ruggedly designed, securely fastened to both units, and equipped with a positive locking mechanism which will prevent separation of the two units except by manual release.
(f) All tank trucks and all trucks pulling tank trailers used to transport anhydrous ammonia over 1,200 gallons water capacity shall be equipped with the following minimum safety equipment which shall be properly maintained and readily available for use:
(g) Each liquid withdrawal opening 2 inches nominal pipe size or larger on transportation tanks and bulk delivery vehicles over 1,200 gallons capacity shall be fitted with a remotely controlled internal shutoff valve of the type listed in Sections 507 (e) (3) through (5). Such tanks over 3,500 gallons capacity shall have 2 remote stations for the valve controls, 1 at each end of the tank and diagonally opposite each other.
One control mechanism at each control station may be used to operate all such remotely controlled valves.
All replacement valves for the above service shall comply with these Orders, if the openings in the tank are adaptable for conversion.
(h) Where excess-flow valves [See Section 507 (e) (2).] are used, all liquid and vapor lines shall be at least full size from the excess-flow valves in the tank to the point of discharge or an additional excess-flow valve or equivalent shall be located as close to the point of pipe size reduction or other restriction as is practical, unless the excess-flow valve in the tank is designed to operate at the reduced flow conditions, in which case the excess-flow valve in the tank may suffice.
Where excess flow valves are used on tank trucks having 2 or more tanks with common loading and/or unloading lines, the common liquid or vapor lines shall be fitted with an excess-flow valve or equivalent in the common line in addition to the excess-flow valve in the tank opening (unless the common line has a cross-sectional area equal to or in excess of the combined areas of the individual tank lines or unless the excess flow valves in the tank are designed to operate at the reduced flow condition, in either of which case the excess-flow valve in the tank may suffice). Where additional excess-flow valves are used in common loading and/or unloading lines, the additional excess-flow valve or equivalent shall be located as close to the point of restriction as is practical.
Note: A quick-closing manually operated valve may be considered equivalent to an excess-flow valve at the point of pipe size reduction or other restriction providing:
(3) The quick-closing valve is located on the tank side of the structure used to secure the line or lines to the tank or vehicle frame.
1. Amendment of subsections (g), (h) and (j) filed 12-8-72 as procedural and organizational; effective upon filing (Register 72, No. 50).
2. Amendment of subsections (a) and (f) and new subsection (k) filed 3-28-75; effective thirtieth day thereafter (Register 75, No. 13).
3. Repealer and new subsection (f) filed 8-6-76; effective thirtieth day thereafter (Register 76, No. 32).