Issue A and B - Exposure Protection Sprinklers - Window Type
Exposure (Outside) Protection Sprinklers are utilized to provide protection from exposure fires on the outside of buildings . The Issue A and B Window Type Exposure Protection Sprinklers are intended for spraying water on window glazing at prescibed spacings and sprinkler locations at a minimum discharge pressure of 7 psi (0,48 bar).
The smaller orifice Issue A Sprinklers are normally used where exposure is light or moderate, the area of coverage is small, or where one horizontal line of window sprinklers is installed at each floor. The larger orifice Issue B Sprinklers are normally used where exposure is severe, or where one horizontal line of sprinklers is used to protect windows at more than one floor level.
It is recommended that the end user be consulted with respect to the suitability of the materials of construction and finish for any given corrosive environment. The effects of ambient temperature, concentration of chemicals, and gas/chemical velocity, should be considered, at a minimum, along with the corrosive nature to which the sprinklers may be exposed.
The Issue A and B Window Type Exposure Protection Sprinklers are a redesignation for the Gem Issue A and B.
Approvals
The Issue A and B Window Type Exposure
Protection Sprinklers are UL
Listed and FM Approved.
Maximum Working Pressure
175 psi (12,1 bar).
Nozzle Type | Orifice Size | Thread Size | K- Factor | |
NFPA | ISO/SI | |||
Issue A | 1/4” | 1/2" | 1.83 | 26,33 |
5/16" | 1/2" | 2.62 | 37,72 | |
3/8" | 1/2" | 4.08 | 58,73 | |
Issue B | 1/2" | 1/2" | 5.76 | 82,93 |
5/8" | 3/4" | 8.64 | 124,39 | |
3/4" | 3/4" | 12.39 | 178,39 |