FM Approved 3053441and UL / CUL listed EX6430. 1/2 " NPT (National National Pipe Thread) American thread fire sprinkler heads Underwriter Laboratories Listed, UL(United States) and ULC(Canada) Listed Nominal 5.6 K-Factor fire sprinkler heads, Dia5mm Glass Bulb Standard Response 155F 68C Max working pressure 175psig /1.2Mpa(12 bar);Factory Hydrostatic Test 100%@ 500psig (3.4Mpa) Automatic fire sprinklers of the frangible bulb type

During a fire conditions, the thermal-sensitive liquid in the glass bulb expands, causing the bulb to shatter, releasing the button and spring seal assembly. Water flowing through the sprinkler orifice strikes the sprinkler deflector, forming a uniform spray pattern to extinguish or control the fire.

Temperature Rating: 155°F (68°C)

Discharge Coefficient: K=5.6(U.S) /80(Metric) 

Nominal Orifice Size:1/2"(15mm) 

Maximum Working Pressure:175psi(12bar) 

Min. Operating Pressure: 7psi (0.48bar) 

Factory Hydrostatic Test: 100%@ 500psi (34.5bar) 

NPT: National Pipe Tapered is common in plumbing and some industrial uses. Sometimes referred to as pipe thread because PVC pipe and schedule 40 pipe are typically threaded in NPT. As its name implies this is a tapered thread so that the outside diameter of the male (ODM) gets smaller towards the end of the fitting and the inside diameter of the female narrows with depth. As the two fittings are threaded together the opposite tapers force thread friction and makes the seal without the use of a gasket.