Before revision: SI units: {| border="0" cellpadding="2" |- |align=where: | |- !align= ΔP |align== available pressure difference, in Pa |- !align=Mg |align== molecular weight of gas, in g/mol |- !align= a |align== atmospheric pressure, in Pa |- !align= h |align== height or distance, in m |- !align= To |align== absolute outside temperature, in K |- !align= Ti |align== absolute inside temperature, in K |} Induced flow The draft (draught in British English) flow rate induced by the stack effect can be calculated with the equation presented below.
After revision: SI units: {| border="0" cellpadding="2" |- |align=where: | |- !align= ΔP |align== available pressure difference, in mmWC |- !align=Mg |align== molecular weight of gas, in g/mol |- !align= a |align== atmospheric pressure, in kPa |- !align= h |align== height or distance, in m |- !align= To |align== absolute outside temperature, in K |- !align= Ti |align== absolute inside temperature, in K |} Induced flow The draft (draught in British English) flow rate induced by the stack effect can be calculated with the equation presented below.