755 MINIMUM FILL
The following tests and specifications apply to articles such as creams, gels, jellies, lotions, ointments, pastes, powders, and aerosols, including pressurized and nonpressurized topical sprays that are packaged in containers in which the labeled content is not more than 150 g or 150 mL.

procedure for dosage forms other than aerosols
For containers labeled by weight, select a sample of 10 filled containers, and remove any labeling that might be altered in weight during the removal of the container contents. Thoroughly cleanse and dry the outside of the containers by a suitable means, and weigh individually. Quantitatively remove the contents from each container, cutting the latter open and washing with a suitable solvent, if necessary, taking care to retain the closure and other parts of each container. Dry, and again weigh each empty container together with its corresponding parts. The difference between the two weights is the net weight of the contents of the container. For containers labeled by volume, pour the contents of 10 containers into 10 suitable graduated cylinders, and allow to drain completely. Record the volume of the contents of each of the 10 containers. The average net content of the 10 containers is not less than the labeled amount, and the net content of any single container is not less than 90% of the labeled amount where the labeled amount is 60 g or 60 mL or less, or not less than 95% of the labeled amount where the labeled amount is more than 60 g or 60 mL but not more than 150 g or 150 mL. If this requirement is not met, determine the content of 20 additional containers. The average content of the 30 containers is not less than the labeled amount, and the net content of not more than 1 of the 30 containers is less than 90% of the labeled amount where the labeled amount is 60 g or 60 mL or less, or less than 95% of the labeled amount where the labeled amount is more than 60 g or 60 mL but not more than 150 g or 150 mL.

procedure for aerosols
Select a sample of 10 filled containers, and remove any labeling that might be altered in weight during the removal of the container contents. Thoroughly cleanse and dry the outsides of the containers by suitable means, and weigh individually. Remove the contents from each container by employing any safe technique (e.g., chill to reduce the internal pressure, remove the valve, and pour). Remove any residual contents with suitable solvents, then rinse with a few portions of methanol. Retain as a unit the container, the valve, and all associated parts, and heat them at 100 for 5 minutes. Cool, and again weigh each of the containers together with its corresponding parts. The difference between the original weight and the weight of the empty aerosol container is the net fill weight. Determine the net fill weight for each container tested. The requirements are met if the net weight of the contents of each of the 10 containers is not less than the labeled amount.
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Topic/Question Contact Expert Committee
General Chapter Desmond G. Hunt, Ph.D.
Senior Scientific Liaison
1-301-816-8341
(GCDF2010) General Chapters - Dosage Forms
USP35–NF30 Page 324