Closed-type wet sprinkler system
This wet pipe system maintains pressurized water throughout the piping network at all times. At their activation temperature, individual sprinkler heads open to spray water onto the fire, while the pressure drop triggers local and monitoring alarms.This highly reliable design constitutes the global industry standard for standard occupancies.Closed-type dry sprinkler system
Compressed air fills the piping between the closed sprinkler head and the dry water flow detector. Heat opens the head, venting this air and dropping system pressure. This pressure drop triggers the detector, which releases water through the sprinkler. This system is used in cold regions where there is a risk of pipes freezing.Closed-type pre-action sprinkler system
This pre-action design isolates water behind the control valve to eliminate sub-freezing risks and accidental discharges caused by mechanical impact to the sprinkler heads. In a fire event, a dedicated detection system trips the pre-action valve, flooding the dry overhead piping network with pressurized water for immediate discharge through the thermally activated heads. Asset managers select this dual-interlock architecture to protect server rooms, IT hubs, and mission-critical spaces where accidental water discharge presents a severe risk to high-value infrastructure.
Open-type sprinkler system
This system uses open-type sprinkler heads without heat-sensing elements, mounted on the ceiling.During a fire event, a dedicated system detector automatically trips the deluge valve—or an operator actuates it manually—to flood the piping network and discharge water simultaneously from all open-type nozzles within the designated zone. It is primarily used in theater stages.

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