Estimation of CH4 emission from landfill: Guidance on the use of methane correction factor (MCF) in different management conditions of solid waste disposal sites (SWDS) has been updated. New default values for the MCF to estimate CH4 emissions from active aeration landfill have been provided by level of landfill management (poorly and well managed). The IPCC Waste Model has been updated according to the refinement. Default values for the fraction of degradable organic carbon which decomposes (DOCf) for different waste components and their uncertainties have been updated, and relevant guidance has been added.