The service life of the gas alarm sensor itself is very short and has a lot to do with the use of the occasion, the international famous brand of industrial products, 6 months to check once, so the household products do not appear to be a strong inspection requirements.
Water heaters, gas stoves and other civilian products installed on the flameout shutdown device, is a one-time factory inspection products.
The following two national standards are used in my work and gas alarm related standards, I do not know if it is useful to you?
GB/T 12474-2008 Method for Determining the Explosive Limit of Combustible Gases in Air
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GB 50493-2009 Petrochemical Combustible and Toxic Gas Detection and Alarm Design Specification
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