Abstract: An improved construction is provided for fluid pressure responsive electrical switching apparatus, which achieves physical miniaturization, quick response time, sensitivity to relatively low levels of change or differential in fluid pressures, adaptability for employment in corrosive environments and under a very wide range of temperature conditions, simplicity and economy of fabrication and assembly, reliability of operation and general versatility for utilization in diverse applications. The improved apparatus involves, besides suitable housing structure that may provide for installation accommodating to various pressure and other conditions dictated by the application, a thin, wafer-like laminated switch assembly peripherally sealed in the housing structure and disposed for direct fluid communication with the fluid whose pressure is to be monitored for the purpose of controlling actuation of the switch assembly.

Abstract: A tubular discharge nozzle for spraying a pressurized fire suppression liquid from immediately beneath a ceiling in a fire sprinkling system is provided with a hollow, dome-shaped, ceiling protective shield disposed to deflect the laterally directed high velocity fluid streams downwardly away from the ceiling while, at the same time, permitting low volume escape of the fluid upwardly from the shield toward the ceiling through slots so located in the shield as to produce low velocity secondary plumes which cravitate exteriorly of the shield to merge with the primary streams and thereby maintain the needed, wide spray pattern below the nozzle-shield unit.