Viking Specific Application Early Suppression Fast Response (ESFR) Pendent Sprinkler VK514 incorporates the capability to suppress specific high-challenge fires. The addition of a larger K-Factor allows protection of higher hazard commodities at greater ceiling heights with lower end-head pressures.  K28.0 sprinklers can provide flexibility of fire protection designs and eliminate the use of in-rack sprinklers when protecting high piled storage of? certain specified materials up to: UL - 43 ft. (13.1 m) with ceilings up to 48 ft. (14.6 m) and FM - 50 ft. (15.2 m) with ceilings up to 55 ft. (16.8 m) OR 45 ft. (13.5 m) with ceilings up to 50 ft. (15.2 m) Viking VK514 ESFR Pendent Sprinklers are primarily intended to protect the following types of storage, which tend to produce severe-challenge fires: palletized and solid pile storage and single, double, and portable open rack storage (no open-top containers or solid shelves). The VK514 is listed to utilize a minimum aisle width of 6’-0” (UL - 43’ storage and FM - 45' storage) or 8’-0” (FM - 50’. storage).