Experimental investigation of in-rack sprinkler parameters for ASRS warehouse protection

Abstract

Warehouses utilizing automatic storage and retrieval systems (ASRS) are widely accepted as a challenging fire scenario because of the taller heights and concentrated storage of goods. Most fire protection system designs will follow NFPA 13 for ceiling and in-rack sprinkler installation in this type of occupancy. The Taiwanese fire code currently prescribes sprinkler requirements for traditional warehouses, but lacks such provisions for ASRS warehouses. The only requirement is a 114 LPM discharge rate as the minimum design standard. On-site surveys of Taiwanese ASRS warehouses revealed that the majority of in-rack sprinkler installations comply with these standards, but spray distribution and fire suppression experiments from this work show that not all compliant systems possess sufficient fire suppression capabilities for the goods below. Many of the sites were found to have installed in-rack sprinklers between the double-row racks. Using this setup, fire suppression experiments showed insufficient fire suppression performance when using standard design values. In-rack sprinkler performance was observed to improve significantly with adjustments to sprinkler positioning, discharge pressure, and sprinkler-to-goods distance. This study provides insight and recommendations into suitable in-rack sprinkler configurations for adequate ASRS warehouse fire protection. Additionally, this study proposes an in-rack sprinkler flowchart that serves as a reference for in-rack sprinkler installation, offering practical guidance to optimize fire suppression performance.