Significant Figures and Their Effects on Inspection

In this Question Line video, Jason answers the following question regarding the effects of significant figures on inspection: 

I’m looking for insights from experienced metrologists on how to ensure the correct measurement resolution when inspecting mechanical parts. In my work, I’ve encountered a dilemma related to the formatting of dimensions on drawings and its impact on selecting the appropriate measurement tools.

Specifically, the ASME Y14.5-2018 standard recommends omitting trailing zeros for dimensions in metric units (e.g. “5 mm” instead of 5.00 mm”). However, I’ve always relied on those extra zeros to gauge the required resolution for my measuring equipment. How do you determine the required resolution for your measuring equipment when trailing zeros are not present on a drawing?

In this video, Jason confirms that the ASME Y14.5 standard does recommend omitting trailing zeroes for dimensions in metric units and discusses the role of significant figures in identifying tolerances for dimensions with unspecified tolerances. He also walks through an example of how to determine the required accuracy of the measurement equipment according to the ASME Y14.43 standard. 

https://youtu.be/OVHPDGdQr1E

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