Tests shall be performed on the final product to determine that it meets the following standards:

(a) Protein concentration. Final product shall conform to one of the following concentrations: 4.0 ±0.25 percent; 5.0 ±0.30 percent; 20.0 ±1.2 percent; and 25.0 ±1.5 percent solution of protein.

(b) Protein composition. At least 96 percent of the total protein in the final product shall be albumin, as determined by a method that has been approved for each manufacturer by the Director, Center for Biologics Evaluation and Research, Food and Drug Administration.

(c) pH. The pH shall be 6.9 ±0.5 when measured in a solution of the final product diluted to a concentration of 1 percent protein with 0.15 molar sodium chloride.

(d) Sodium concentration. The sodium concentration of the final product shall be 130 to 160 milliequivalents per liter.

(e) Potassium concentration. The potassium concentration of the final product shall not exceed 2 milliequivalents per liter.

(f) Heat stability. A final container sample of Albumin (Human) shall remain unchanged, as determined by visual inspection, after heating at 57 °C for 50 hours, when compared to its control consisting of a sample, from the same lot, which has not undergone this heating.