Ratios and Traceability

Again, the "stated uncertainties" are preferably according to the GUM, but may be tolerances or specifications if they conform to 5.10.4.1 and 5.10.4.2.

There are no defined requirements to indicate whether a TUR of a given ratio is required for the unbroken chain. If the uncertainties are stated, the uncertainty of a standard at any given level may be calculated, so TUR doesn't really matter.