Abstract: A power supply for providing excitation to notification appliance circuits (NACs) in fire alarm applications meets revised national and international requirements for both NAC drive and auxiliary load drive tasks with a single circuit configuration. The requirements stipulate ability to tolerate inrush when activating strobe lights and horns of ten times the nominal output, while limiting short-circuit drive in AUX mode to eight amperes after five seconds. The novel power supply improves on the requirements, first by continuously testing for overcurrent NAC status and signaling faults in real time, and second by shutting off AUX drive in event of a short and retrying periodically without a requirement for manual reset. Thus testing for wiring errors is rendered safer and nondestructive, and correction of a wiring error can be quicker.

Abstract: An insulation system for protecting metal membranes that seal a fluidization grid floor in a process vessel to the vessel wall or to a standpipe in the vessel. The seal is comprised of erosion-resistant castable refractory, compressible insulation and metal in specifically arranged layers and in a manner such that expansion of the grid floor does not stress the castable refractory.

Abstract: A fireproofing composition comprised of a low density matrix material, such as rigid foamed sodium silicate, having an expandable hydrated mineral material such as unexpanded vermiculite or unexpanded perlite incorporated therein.

Abstract: An alkali metal silicate foam composition comprising preferably sodium silicate, cementing agent such as sodium silicofluoride, gelling agent such as linoleic acid and filler such as glass fiber mixed with water and blowing agent to provide foams having high strength, high water resistance and low shrinkage upon curing. Amides and halo-alcohols are used as gelling agents in preferred compositions for exceptional strength and water resistance. Vermiculite and perlite are preferred fillers for a low shrinkage foam composition.