FED-STD-791 Lubricants, Liquid Fuels, And Related Products, Testing Method OfThis test method standard is composed of standard test methods for sampling, inspecting and testing lubricants, liquid fuels and related products. It is issued pursuant to the Federal Property and Administration Services Act of 1949, as amended and its application to the purchase of commodities referred to herein is mandatory on all Federal agencies.

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'�NOTE:This draft dated 15 April 2006' by DasH - Page 74 of 460

FED-STD-791D

4.5 Vacuum pump, capable of reducing the pressure to at least 1.0 mm of mercury.

4.6 Water bath, capable of maintaining a temperature of 80�  2�C (175�  5�F) and

sufficient size to contain the test cell.

4.7 Laboratory safety shield, constructed of either safety glass or wire reinforced plastic.

5. MATERIALS

5.1 CAUTION: SOME MATERIALS ARE TOXIC AND HAZARDOUS. The

materials references and standards listed in this section must be handled carefully. Federal Test

Method 10000, Material Handling Safety Precautions, is a reference which lists all toxic and

hazardous materials cited in FTMS 791. The synonyms, life hazard, flammability, handling and

storage precautions, emergency treatment and measures, and spill practices of each chemical are

explained.

5.2 Cleaning solution glass (concentrated sulfuric acid [3,0,2] saturated with potassium

dichromate, technical grade).

5.3 Detergent for cleaning glassware [u,u,u].

6. PROCEDURE

6.1 Cleaning test cell. Clean the test cell by scrubbing with a suitable detergent and rinse

with distilled water. Prior to the introduction of the sample into the test cell, the cell shall be

rinsed in hot potassium dichromate-sulfuric acid cleaning solution, thoroughly rinsed in distilled

water, and dried in an oven at 107�  2.5�C (225�  5�F) for 1 h.

6.2 Preheat and adjust heater temperature to 260�  1�C (500�  2�F).

6.3 Perform duplicate test procedures of 6.4 through 6.13.

6.4 Filter the sample through a nominal 10-�m filter paper to remove particle

contaminants.

6.5 Introduce 20 mL of the filtered sample below the constricted area of the test cell with

the aid of the hypodermic syringe.

NOTE: This syringe is capable of delivering 20.0 0.5 mL of sample which is within the

accuracy required by this test procedure.

6.6 Connect the filled test cell to the vacuum pump and degas the cell and its contents,

while shaking gently for at least 5 min or until foam no longer persists.

6.7 Place the test cell, while still connected to the operating vacuum pump, in a water

bath maintained at 80� 2�C (175�  5�F) for 5 min. Remove the cell from the bath, shake