Mettler Toledo’s Weighing Standard Ensures Compliance with USP Revisions

On the 3rd June, 2013, United States Pharmacopeia (USP) published revisions to mandatory Chapter 41 on balances and advisory Chapter 1251. With only six months to comply, Mettler Toledo’s global weighing standard, GWP®, can help pharmaceutical manufacturers and suppliers to meet the new requirements. The revisions define modified balance test procedures for the US pharmaceutical industry and companies exporting to the US. With the revised chapters becoming official on 1st December, 2013, Mettler Toledo is offering a free on-demand webinar to explain how balance quality management will be affected, focusing on the determination of minimum weight and execution of routine testing. In addition, there is also a wealth of further information on the website.

Recent revisions to USP General Chapters 41 (‘Balances’) and 1251 (‘Weighing on an Analytical Balance’) attempt to clarify and simplify previous descriptions and update to reflect state-of-the-art weighing practices. The aim is to help US pharmaceutical manufacturers and suppliers to ensure weighing accuracy and eliminate unnecessary over-testing. Mettler Toledo’s Global Weighing Standard: Good Weighing Practice™ (GWP®) can help consumers put the new standards into practice in a structured and
effective way.

Demanding Balance Assessment
The new requirements of General Chapter 41 are mandatory. The revised chapter details a relatively demanding balance assessment, describing accuracy and repeatability tests for calibrated balances used
to weigh analytes for quantitative measures. Test weight selection criteria have been modified, as weights below 5% of the instrument capacity cannot adequately assess systematic deviations.

Achieve Time Savings
without Compromising Accuracy General Chapter 1251 provides additional clarification and extends the scope to any balance used for an analytical procedure. It details that balance performance verification should be carried out using a risk-based approach. Crucially, it is recommended to only weigh net samples sufficiently above the minimum weight to account for balance performance fluctuations. This requirement is clearly applied to the sample weight, not the tare vessel. Also, daily testing ecommendations have been dropped. This change is expected to provide significant time and cost savings.

Consistent Quality
with GWP® Verification Mettler Toledo’s GWP® - The Weighing Standard - can help manufacturers implement the new USP regulations. GWP® Verification is a unique, risk-based service that helps eliminate redundant or erroneous testing in weighing applications. By determining the minimum weight and measurement uncertainty for every balance or scale used, manufacturers can optimise SOPs, ensure consistent product quality and pass audits, whilst avoiding costly litigation resulting from an out-of-specification product.

Mettler Toledo’s free On-Demand Webinar explaining the implications of these USP revisions can be
viewed at: www.mt.com/gwp-usp-webinar To download the white paper, watch videos, register for an
e-Learning course or download a summary of the revised USP weighing chapters visit: mt.com/lab-usp