Key Takeaways: Combining Uncertainty Methodology: Components are combined using the Root Sum of the Squares (RSS) method, also known as the Law of Propagation of Uncertainty. Pre-requisite: All components must be expressed as standard uncertainties (u) in the same units before combining. Sensitivity Coefficients: Essential for converting different units (e.g., Temperature to Length) so they […]
Survey I am looking to expand my services by offering affordable product options. Please complete this anonymous survey. It will only take 60 seconds! Thank you. Background Lately, I have been thinking of how to expand my business to attract new customers while helping my current clients. Then, it hit me! I should […]
Introduction Calibration interval analysis has been a popular topic the past few months. From direct questions to LinkedIn discussions, people seem to have a lot of questions regarding calibration interval analysis. As a result, I created a post on the 5 Best Calibration Intervals Guides. Now, I am proposing a new calibration interval analysis method. […]
Recently, there have been a lot questions and discussion regarding calibration intervals. People want to know how to establish and adjust calibration intervals appropriately. Well, there is not one single method that will apply to all or most situations. Therefore, I recommend that you study as many methods of Calibration Interval Analysis as possible to […]
I was answering questions on LinkedIn the other day and came across an individual who wanted to know how to evaluate their suppliers in accordance with section 4.6.4 of the ISO/IEC 17025:2005 standard. Most of the answers posted involved elaborate evaluations and superficial criteria that would not be applicable to most laboratories for evaluating their […]
Assessing Conformance to Specifications When a client requires a statement of conformance to predetermined specifications, there are several cases where the uncertainty in measurement has an influence on the statement of conformance. To properly assess conformance, add(subtract) the estimated expanded uncertainty to(from) the measurement result and determine which of the four following scenarios apply. […]
Quantifying UUT resolution uncertainty can vary significantly depending upon a device’s design, functionality, and operation. The resolution of a digital device may not be evaluated in the same manner as an analog device or artifact. Additionally, the resolution of similar devices may vary depending on how it is used. This makes the evaluation of resolution uncertainty […]
Propagation of Uncertainty Propagation of uncertainty is a method that transmits the uncertainties of independent variables through an equation to estimate the uncertainty of the final calculation. When physical quantities cannot be measured with a single direct measurement, we typically perform indirect measurements of two or more quantities to calculate the desired measurement result. By […]
Propagation of uncertainty is an important aspect of uncertainty analysis. It is a method that transmits the uncertainties of independent variables through an equation to estimate the uncertainty of the final calculation. Commonly practiced in error and uncertainty analysis, the method is useful for estimating uncertainty where physical quantities cannot be measured directly. Indirect […]
Need to find an ISO 17025 Accredited Laboratory? Today, I answered a question on LinkedIn and thought it would be an excellent post to share on my blog. The post asked a question that I encounter quite often, “Does anyone know where I can find a list of metrology labs in the US?” Well, I […]
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