A1.2.1 Fig. A1.1 shows that water is soluble in toluene to a
significant extent. The percentage of water that will dissolve
increases as the temperature is increased from about 0.03 % at
21°C (70°F) to about 0.17 % at 70°C (158°F). Toluene, as
normally supplied, is relatively dry and, if used in the asreceived
condition, will dissolve a portion or even all the water
present in a fuel oil sample. This dissolution would reduce the
apparent sediment and water level in the fuel oil sample. To
determine water and sediment accurately by centrifuge on a
fuel oil sample, the toluene must first be saturated at the
centrifuge test temperature.