- Chapter 41 states that accurate weighing must be performed using a calibrated balance. A more demanding balance assessment is introduced. Repeatability and accuracy tests are defined, with acceptance limits and permissible test weights. The WhitePaper “Weighing According to US Pharmacopeia” explains the requirements in more detail. Standard operating procedures for balance testing are available to download for free.
- Chapter 1251 revisions focus on balance qualification and operation, including the importance of "minimum weight". A daily balance check, typically performed in the pharmaceutical industry, is no longer mandatory. Instead, the type and frequency of testing should be based on the risk and process tolerance of the application. Performing the right tests at the right intervals ensures high-quality results and potentially saves time and money by eliminating unnecessary testing! Watch the video Three Key Things about the USP revisions on weighing.
- Chapter 1251 also introduces "gravimetric dosing", a state-of-the-art weighing methodology for analytical standard and sample preparation. This method involves weighing of the sample and diluent, resulting in concentration units of mg/g.
This eLearning course provides all the information required to understand the 2013 revisions to USP General Chapters 41 (Balances) and 1251 (Weighing on an analytical balance). A certificate will be automatically generated upon completion of the course, which should take 60-90 minutes.
The course covers:
- The revisions to USP 41 and 1251
- The impact this has on your weighing equipment
- Recommended frequency of performance qualification (PQ)
- The significance of the minimum weight of a balance – and how to calculate it
- Repeatability and accuracy requirements
- The importance of using a calibrated balance
What is USP?
The United States Pharmacopeia (USP) is a scientific, non-governmental organization which sets the official public standards for drugs and drug products in the US. These standards include identity, strength, quality and purity of substances manufactured, distributed and consumed in the US. The USP drug standards are used in more than 140 countries, and are enforceable in the US by the Food and Drug Administration (FDA).
What are USP Chapters 41 and 1251 about?
- USP General Chapter 41 "Balances" is mandatory and states the requirements for balances used for materials that must be accurately weighed. Weighing should be performed using a balance that is calibrated over the operating range and meets the requirements defined for repeatability and accuracy.
- USP General Chapter 1251 "Weighing on an Analytical Balance" is a guideline applicable to balances used in all analytical procedures. It provides information on installation and operational qualification (IQ/OQ), performance qualification and balance checks (routine testing), minimum weight and balance operation. See webinar on Calibration and Qualification of Laboratory Instruments.