Ash Shrinkage Starting Temperature (SST) - This occurs when the area of the test piece of biomass ash falls below 95% of the original test piece area.
Ash Deformation Temperature (DT) - The temperature at which the first signs of rounding of the edges of the test piece occurs due to melting.
Ash Hemisphere Temperature (HT) - When the test piece of biomass ash forms a hemisphere (i.e. the height becomes equal to half the base diameter).
Ash Flow Temperature (FT) - The temperature at which the biomass ash is spread out over the supporting tile in a layer, the height of which is half of the test piece at the hemisphere temperature.