ASTM D5772 Standard Test Method for Cloud Point of Petroleum Products and Liquid Fuels (Linear Cooling Rate Method)
6. Apparatus
6.1 Automatic Apparatus - The automatic cloud point apparatus described in Annex A1 consists of a microprocessor-controlled measuring unit that is capable of heating, cooling, optically observing the appearance of the automatic cloud point, and recording the temperature of the specimen. The apparatus shall be equipped with a digital display, cooling/heating block assembly, optical light barrier assembly, and a test cell ofthe approximate dimensions listed in Annex A1, and contain a temperature measuring device.

6.2 Beaker, glass or plastic (disposable) (50 mL), for containing the sample prior to introduction into the test cell.

6.3 Circulating Bath, a refrigeration unit equipped with a circulating pump capable of maintaining a temperature at least 20 °C lower than the lowest expected cloud point to be measured.

7. Reagents and Materials
7.1 Cleaning Solvents, suitable for cleaning and drying the test cell, such as petroleum naphtha and acetone. (Warning - Flammable. Liquid causes eye burns. Vapor is harmful. May be fatal or cause blindness if swallowed or inhaled.)

7.2 Methyl Alcohol, anhydrous, for use as cooling medium in circulating bath.

7.3 Lint-free filter paper may be used as a drying medium.