The operator may determine the activity data of biomass source streams without using tiers and providing analytical evidence regarding the biomass content, where that source stream consists exclusively of biomass and the operator can ensure that it is not contaminated with other materials or fuels.

The emission factor of biomass shall be zero.

The emission factor of a mixed fuel or material shall be calculated and reported as the preliminary emission factor determined in accordance with Article 30 multiplied by the fossil fraction of the fuel or material.

Peat, xylite and fossil fractions of mixed fuels or materials shall not be considered biomass.

Where the biomass fraction of mixed fuels or materials is equal or higher than 97 %, or where due to the amount of the emissions associated with the fossil fraction of the fuel or material it qualifies as a de-minimis source stream, the competent authority may allow the operator to apply no-tier methodologies, including the energy balance method, for determining activity data and relevant calculation factors, unless the respective value is to be used for the subtraction of biomass derived CO₂ from emissions determined by means of continuous emission measurement.