60.5.1.9.1
Guard posts or other approved means shall be provided to protect the following where subject to vehicular damage:
1. Storage tanks and connected piping, valves, and fittings
2. Storage areas containing tanks or portable containers except where the exposing vehicles are powered industrial trucks used for transporting the hazardous materials
3. Use areas
60.5.1.9.2
Where guard posts are installed, the posts shall meet the following criteria:
1. They shall be constructed of steel not less than 4 in. (102 mm) in diameter and concrete filled.
2. They shall be spaced not more than 4 ft (1.2 m) between posts on center.
3. They shall be set not less than 3 ft (0.9 m) deep in a concrete footing of not less than a 15 in. (381 mm) diameter.
4. They shall be set with the top of the posts not less than 3 ft (0.9 m) above ground.
5. They shall be located not less than 3 ft (0.9 m) from the tank.