Section 914.3.2 of the International Fire Code is hereby amended to read as follows:

914.3.2 Secondary water source. A secondary on-site water source shall be provided for high-rise building as follows:

1. High-rise buildings containing R or B occupancy only shall be provided with a net useable volume of 15,000 gallons.

2. High-rise buildings containing an S-2 occupancy shall be provided with a net useable volume of 40,000 gallons.

3. High-rise buildings containing an M occupancy shall be provided with a net useable volume of 50,000 gallons.

4. Multi high-rise complexes that are less than 420 feet in height may share a common secondary water source by combining the highest demand of number 2 or 3 above, with number 1 above. Only one parking/retail area and 2 high-rise buildings may share a common secondary water source.

An acceptable alternative to items 1 through 4 above is to prove a calculated net useable volume capable of meeting the hydraulically calculated sprinkler demand, including the total (combined inside and outside) hose stream requirement, as per NFPA 13. The duration of the calculated source shall have a duration of not less than 30 minutes for buildings with light hazard occupancies only and a 60-minute duration for buildings with ordinary hazard occupancies as defined by NFPA 13.

Exception: Existing buildings, including those undergoing substantial renovation.