The minimum ventilation rate required by Sentence 2.4.2.5.(1) is intended to limit the concentrations of flammable gases and toxic gases produced by the decomposition of liquid manure. Higher ventilation rates may be necessary to promote farm animal health and production. Where requested by the authority having jurisdiction, compliance with Clauses 2.4.2.5.(1)(a) and (b) can be demonstrated through periodic in situ monitoring of gas concentrations or through calculation of gas concentrations using a reliable method (such as that described in the following publication: Massé, D.I., Croteau, F., Patni, N.K. and Masse, L. Methane Emissions from Dairy Cow and Swine Manure Slurries Stored at 10°C and 15°C. Canadian Biosystems Engineering, Vol. 45, pp. 6.1–6.6, 2003).