78 DBS-BA-e-131112.7 Drying temperatureBear in mind the following factors when setting the drying temperature:Surface of the sample:Compared with powdery or grainy samples, liquid and spreadable samples have asmaller surface for the transmission of heat energy.The use of a glass fibre filter improves the heat application.Colour of sample:Light-coloured samples reflect more heat radiation than dark ones and thereforerequire a higher drying temperature.Availability of volatile substances:The better and faster the water or other volatile substances can be disposed, thelower a drying temperature is required. If water is difficult to get to (e. g. insynthetics), it has to be calcined at high temperatures (the higher the temperature,the higher the water vapour pressure).Results equivalent to other moisture analysing methods (e. g. drying chamber) canbe achieved by experimentally optimising the setting parameters such astemperature, heating level and shutoff criteria.12.8 Recommendations / GuidelinesPrepare standard sample:- Crush sample, as required, and spread it evenly in the aluminium dish.Prepare special samples:- For sensitive or hard to spread test materials (e. g. mercury) a glass fibre filteris available for use.- Apply the sample equally on the glass fibre filter and cover it with a secondglass fibre filter.- The glass fibre filter is also useful as a protection when splashing materialsare dealt with (each splash falsifies the final result).