A fire hazardous area should include any of the following:
- The area within 30 ft (9.0 m) horizontally and 40 ft (12.0 m) vertically of equipment that has a high fire potential.
- The area within 30 ft (9.0 m) horizontally and 40 ft (12.0 m) vertically of the edge of a drainage ditch or swale/ditch/trough that serves to transport spills from high fire potential equipment to a remote impounding basin.
- For tanks, spheres and spheroids, containing flammable material, the fire hazardous area should extend to the dike wall, or 30 ft (9.0 m) from the storage vessel, whichever is greater.
- For rotating equipment, the 30 ft (9.0 m) horizontal and 40 ft (12.0 m) vertical distance should be taken from the expected source of leakage.
- For marine docks where flammable liquids are handled, the fire hazardous area should extend 100 ft (30 m) horizontally from the manifolds or loading connections on the pier deck.
- When deficiencies in equipment spacing (e.g. pumps are located under pipe rack) and/or unit drainage (e.g. drainage flows under pipe rack), the project team should evaluate if expanding the fire hazardous area is warranted.