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and 4.50 ± 0.025 milliliter in the second case. The apparatus shall not be used if any of these
limits is exceeded.

3.3.5 Test Procedure
3.3.5.1 The apparatus shall be chemically cleaned before any test, to remove surface films
and debris which may hinder free drainage of water in the test apparatus.
3.3.5.2 Thereafter, test sample quantity shall be selected in accordance with paragraph
3.3.3 above, to which sufficient quantity of xylene shall be added to make the total volume
of xylene 400 milliliters. The mixture shall be stirred with the use of a magnetic stirrer to
reduce bumping, after which the apparatus shall be assembled as shown in the figure in
Appendix I such that it is liquid and vapour tight. A suitable drying tube shall be inserted on
the condenser to avoid ingress of atmospheric condensation. Water at 20˚C to 25˚C shall
then be circulated through the condenser jacket. The flask shall then be graduated and the
water condensation in the trap observed until it has attained a constant level indicating
that all the water content in the sample has been boiled off.
3.3.5.2 Thereafter, the trap and contents shall be allowed to cool down to 2ᵒC. Any water
clinging to the walls of the trap shall be dislodged into the water layer with the use of a
Teflon Scraper. The volume of water thus collected in the trap shall be read to the nearest
0.025 milliliter after which the percentage water cut of the sample is calculated as
illustrated below;

3.3.6 Calculation
The water cut of the sample is deduced from the following equation:
Volume % =
(Volume of water in Trap,ml)− (Solvent blank,ml)
Volume of Test Sample,ml
* 100
This shall be expressed to the nearest 0.025 %.
3.3.7 Precision Requirement
3.3.7.1 Both the repeatability and reproducibility range of this method shall be stipulated in
the aforementioned standards. The repeatability and reproducibility of measurement with
each apparatus shall be tested at the frequencies specified by the respective manufacturers
of the equipment.