Balance Academy: The USP 41 Balance

Balance Academy: The USP 41 Balance

Way back in December of 2013, the new regulations of USP chapter 141 went into full effect.

Way back in December of 2013, the new regulations of USP chapter 141 went into full effect. Here in the United States, this chapter of practices is mandatory, and its implementation is overseen by the FDA or the Food and Drug Administration. However, it basically keeps revolving around one essential procedure, which is weighing accurately. Read on to learn about the USP 41 balance and how it affects your laboratory’s day-to-day practices!

The Area of Application

So far, the USP chapter 41 was titled “weights and balances.” When it was revised and released in 2013, it was shortened to “balances,” which accurately indicates the chapter’s main area of application. Accordingly, Chapter 41 doesn’t refer to the minimum sample weights anymore. Instead, it defines the terms “accuracy” and “repeatability.” These are both concepts that are important since they together represent the operating range of your lab balance. The newest USP regulations require that all balances used for weighing, even for pharmaceutical weighing, have to be calibrated.

How Repeatability is Defined

According to the newest USP Chapter 41, repeatability defines the main starting point of a balance’s operating range. So, how do you calculate it then? The folks at the Lab People can help you with that. The higher you will go in a balance’s operating range, the more accurate it will be, relatively speaking. Your results will be in a much similar range as with your parameters formerly used in this type of calculation, so don’t expect any profound changes.

How Accuracy Works According to USP 41

In order to test your balance’s accuracy, Chapter 41 requires users to use test weights that have a mass between 5% and 100% of the balance’s maximum capacity. The USP describes the quality of the weights to be used for these types of tests. This means you’ll have to use a calibrated weight to prove that the uncertainty of that weight is true. However, you don’t need to use any higher class weights. OIML Class F1 and F2 weights usually work just as well too.

The Lab People and The USP 41 Balance

If you need calibration services for ISO 17025 and other accredited services for your pipettes and balances, come visit the Lab People today! We provide services on-site in Maryland, Virginia, West Virginia, Washington DC, Delaware, Pennsylvania, North Carolina, Tennessee, Kentucky, and Georgia!


The Lab People Inc. is a trusted provider of laboratory equipment, services, supplies, and rental equipment for you and your laboratory. As an ISO 17025 accredited service organization, we stand behind our services with 100% satisfaction guaranteed for all of our customers. We offer on-site and off-site calibration services for balances, pipettes, moisture analyzers, force measurement, test weights, and more. Services include preventative maintenance, SQ-Min, IQOQ, repairs, legal for trace/placed in service, verification, and more.

For more information about how we can assist you, visit our websiteemail us, or give us a call at 1-800-296-2001!

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This entry was posted on Friday, July 29th, 2022 at 12:49 pm. Both comments and pings are currently closed.

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