O-Ring seals are commonly used in pharmaceutical manufacturing to ensure the integrity of equipment and prevent contamination. In the United States Pharmacopeia (USP) Chapter 661.4, specific requirements for O-Ring seals are outlined to ensure compliance with industry standards.

USP 661.4 sets forth guidelines for the selection, testing, and use of O-Ring seals in pharmaceutical equipment. These seals must meet certain criteria, such as being made from materials that are compatible with pharmaceutical products and having the ability to maintain a seal under various conditions.

Manufacturers of O-Ring seals must also provide documentation demonstrating compliance with USP 661.4, including information on the materials used, testing procedures, and performance characteristics. This helps to ensure the safety and efficacy of pharmaceutical products by preventing contamination and maintaining product integrity.