 Many types of meters also register air flows, which can lead to over-registration of consumption, especially in systems with intermittent supply, when water supply is re-established and the incoming water pushes air through the meters.Water meters do not distinguish between air and water both are counted as fluid.There are 2 regulations where water companies and meter manufacturers do not comply and charge air for water

There is disagreement as to the effect of metering and water pricing on water consumption.The price elasticity of metered water demand varies greatly depending on local conditions.The effect of volumetric water pricing on consumption tends to be higher if the water bill represents a significant portion of household expenditures.