16.3.1 Two pieces of noncorrosive household window screen measuring 127mm x 127 mm (5 in. x 5 in.).

16.3.1.2 A shallow pan measuring 305 mm x 305 mm (12 in. by 12 in.) and containing two 76 mm (3 in.) high rigid blocks.

16.3.3 A balance accurate to 0.01 gram.

16.3.4 Thickness device consistent with Section 8.1.2

16.6.1 For each specimen, raise the presser foot on the thickness device and place the specimen flat between the presser foot and the anvil.

16.6.2 Gently release the presser foot and allow it to rest on the specimen for 5 seconds.

16.6.3 Record the initial thickness, Ti, to the nearest .0254 mm (0.001 in.).

16.6.4 Place the specimen between the two No. 17 gage wire mesh screens that have been soaked in water for a minimum of 1 hour. Connect the screen corners loosely to hold the test specimen in place without compressing the specimen material.

16.6.5 Immerse the test specimen in the screen assembly in deionized water for 24 ± 0.25 hours.

16.6.6 After the soaking period, remove the assembly from the water, rest it upon the blocks and allow it to drip-drain in a horizontal position for 10 minutes.

16.6.7 Remove the specimen from the screen and measure its thickness, Tf.

Note 8: Care should be exercised to maintain specimen integrity and preserve all material components during removal from screen supports. Lost specimen fibers, threads or other components may significantly impact final results.

16.6.8 Calculate the percent thickness change as follows:

% Thickness Change = 100((Tf-Ti)/Ti)

16.6.9 Repeat the procedure for all ten test specimens.