Manufacturer: Yamato Protec Corporation
Model: Water Discharge Type Sprinkler System

Application

Water-sprinkler systems protect high-ceilinged, open atrium spaces like hotels, theaters, and malls. Wall-mounted sprinkler heads cover wide areas, working with fire detectors to create an intelligent, comprehensive protection system. Once a detector senses fire, the control unit triggers a powerful water discharge for fast suppression. Continuous technological innovations keep improving this water discharge performance.

Types of sprinkler heads

Closed head				Open-type head	Water spray type head
Head with heat-sensitive element				Head without a heat-sensitive element Discharge pressure of 0.1 MPa or higher and discharge rate of 80 L/min or higher	Conventional water cannons, side-wall type watering heads, etc. Discharge rate of 5 L/min/m² (10 L/min/m² in areas where designated combustible materials are stored or handled) or more.
Standard head			Side-wall type head
Heads distributed in a circle centered on the axis			Heads distributed in a semicircle centered on the axis Discharge pressure of 0.1 MPa or higher and discharge rate of 80 L/min or higher
1 type	2 types	Small-compartment head
Sensitivity type 1, effective spray radius 2.6m or more. Discharge pressure of 0.1 MPa or higher and discharge rate of 80 L/min or higher	There are two sensitivity types, and the effective watering radius is 2.3m. Discharge pressure of 0.1 MPa or higher and discharge rate of 80 L/min or higher Its main use is as a sensing head.	Sensitivity type 1, effective spray radius 2.6m or less and 13m² or less Discharge pressure of 0.1 MPa or higher and discharge rate of 50 L/min or higher Large watering angle

Types of sprinkler systems

Sprinklers with water-spraying heads, etc.

When the detector detects a fire, the control unit activates, and a powerful stream of water from the spray head extinguishes the fire in a short time. Fire protection engineers deploy this deluge architecture to protect high-clearance, open-atrium environments—including commercial hospitality venues, large-scale retail complexes, and performing arts centers.”

Standards and evaluation of sprinkler systems using water discharge type, etc.

The Fire and Disaster Management Agency (FDMA) enacted a new regulatory baseline via Notification No. 6 in August 1996, mandating compliance by April 1, 1997. To complement this, the Fire Prevention Bureau published Notification No. 175 in September 1996, which defines the operational protocols for water-spraying systems.
Today, AHJs (Authorities Having Jurisdiction) audit water-spraying installations against rigorous functional, mechanical, and spatial criteria—particularly in high-clearance, arson-targeted occupancies. Depending on the design’s alignment with these codes, inspectors assign either a ‘Category 1’ or ‘Category 2’ compliance rating.
Grade 1

Evaluation No. 2