e.stieferman:
Sorry for the delay. The way to verify sensors you purchase are within their calibration window, look at the NIST traceable certificate of calibration that comes with each pack of sensors. This should be at the bottom of each package you purchase. There will be a two year span listed on the bottom. As far as the "certified" portion on the f2170reports, this is option is temporarily unavailable. We are working on an issue that was identified recently and hope to have it back online shortly. Sorry for any inconvenience.
Jason