Why are monitors installed under kitchen sinks?
There has been no evidence of large volumes of gas accumulating in a room of a house in this estate. Methane is lighter than air and will dissipate quickly unless it is allowed to accumulate in a confined space. The kitchen cupboard is a confined space and would allow very small amounts of methane to be detected long before it could accumulate to any significant level. There are limited penetrations through a slab, one of which is the waste pipe to the kitchen sink. While these are often sealed as a part of the building process it is recognised as a potential pathway for gas to enter the cupboard. What is the percentage of gas to air for it to be dangerous? When methane is between 5% and 15% by volume in a confined space then it is considered to be within the explosive range. For an explosion to occur there must be an ignition source such as a flame or spark. All of these conditions are necessary for it to be considered dangerous. Monitor alarms are set to go off at 1% volume of air (2
