– Determine vessel diameter, product, pressure, and potential fire scenario (jet fire vs. pool fire).
| Feature | NFPA 15 | API RP 2030 | |--------|---------|--------------| | Vessel support leg protection | Not detailed | Detailed with minimum spray density | | Spherical tank protection | General guidance | Specific nozzle aiming angles | | Wind effects on spray pattern | Not addressed | Correction factors for >6 m/s winds | | Fire-resistant valve protection | No | Yes (cryogenic & high temp) | | Inspection frequency | Annual | Semi-annual for corrosive environments |
– Tank size must hold 60 minutes of flow unless a municipal hydrant system provides backup (Section 9).
– Using the application rates from Section 5 of the PDF, multiply by the exposed surface area. For spheres, API RP 2030 allows reduction for areas shielded by adjacent spheres.
– The standard refers to NFPA 15 for hydraulic calculations but mandates a minimum residual pressure of 50 psi (3.4 bar) at the farthest nozzle.