Abstract: An apparatus and method for in situ calibration of a metering device (21) in a gas manifold or plumbing system. A calibrated gas source and inlet (17) are provided. Connected to the calibrated gas source is a first three way valve. The first three way valve is connected to an inlet of the metering device (21) with an outlet connected to a second three way valve. The second three way valve is connected to both a reaction chamber or an exhaust. A calibration gas is allowed to flow through the calibration inlet (17), through the first three way valve, through the metering device (21), and through the second three way valve so as to calibrate the metering device to the calibrated gas source.

Abstract: This invention relates to impregnated oil filter substrate and to oil filters containing such impregnated substrates that require a single cure and can pass a hot oil immersion test, said filter substrate being impregnated with a water-based binder comprising a latex containing at least 20% polymerized vinyl chloride in the latex solids, said latex being a copolymer of vinyl chloride, 30 to 60% lower alkyl acrylate, and one or more comonomers selected from acrylic acid and N-methylol acrylamide, said comonomers being used in an amount of up to 5%, based on the weight of the monomers used to make the latex; said binder also containing 5 to 20 parts of a cross-linking resin per 100 weight parts of latex solids and 5 to 20% catalyst for the cross-linking resin based on the weight of the cross-linking resin.