Standards profile: EA-4/02, the uncertainty guide that shows its work

The GUM defines the framework; EA-4/02 shows the homework. The European co-operation for Accreditation's mandatory uncertainty guide applies GUM methods to routine calibration with a directness working labs appreciate — model, budget table, coverage factor, done — and then does something rarer: a supplement of fully worked examples.

The examples span the bread-and-butter of a commercial lab — weights, gauge blocks, thermometers, multimeters, torque — each carried from measurement model to reported expanded uncertainty. For a lab building its first budgets, copying the STRUCTURE of an EA-4/02 example (not its numbers) is the fastest honest route to a defensible template.

The guide is freely downloadable, and its treatment of when k=2 suffices versus when effective degrees of freedom demand more echoes the coverage-factor discussion in our Q&A section. Read it alongside the GUM itself: one supplies rigor, the other supplies rhythm.