In areas using HVLS fans, where must the fans be located in regards to sprinkler...

According to NFPA 13, HVLS fans shall be centered approximately between four adjacent sprinklers to avoid interference with the sprinkler discharge pattern and to provide adequate clearance from the sprinkler deflectors. This requirement applies to both standard and ESFR sprinklers, and the fans shall be interlocked to shut down immediately upon a waterflow alarm.

References: NFPA 13, 2019 edition, section 11.1.71; NFPA 13 Handbook, 2019 edition, section 11.1.72; NFPA 13 Guidelines for Placing HVLS Fans in Sprinkler Protected Buildings; HVLS Fans and Fire Sprinklers