Transition to newly published guidelines are getting compulsory from Jan’2020, these have already started creating pangs in the stomach of the calibration lab owners and managers. it has inevitably added more overhead cost on account of strict governance and control guidelines.
Calibration labs was already under pressure to optimise cost of calibration and on turnaround of certificates. Most of these labs are still working on paper and rely on Excel based calculations and MS-Office based certificates. Following two guidelines are the reason of their worry,
1. Decision Rule Applicability
New rules regarding decision rule applicability on (at least legal metro logy and instruments where other standards have laid down limits of acceptable and permissible limits), At the moment calibration labs stating conformity without specifying any explanation behind the decision. With this new rule, calibration labs have to explain the reason of their decision and method they choose to arrive at the decision.

It also states requirement of minimum accuracy that is expected of standard that could be used to calibrate DUC/UUC.

2. Determining Re-Calibration interval
Guidelines relating to finding Re-calibration interval Requires to choose Re-calibration interval using any of the four methods, 2017 guidelines have specified and detailed method used for finding calibration interval.
i. Method 1: Automatic adjustment or “staircase” (calendar-time) : Calibration is done on routine basis in a set frequency however the frequency need to be revised (extended or shortened ) depending upon reported drift, stability or permissible error.
ii. Method 2: Control chart (calendar-time) : Using control charts and seeing deviation of error over the timeline
iii. Method 3: In-Use time, implies that labs need to keep a log of usage of instruments and depending upon usage, a calibration interval could be intuitively planned.
iv. In-Service checking, or “black box” testing, Critical parameters are checked frequently (once a day or even more often) , or preferably, or a tool kit (“Black-box”) specifically assembled to check the selected parameters. If the instrument is found to be outside the maximum permissible error by the “black box”, it is returned for a full calibration.

Well, it is not a new guideline as labs are at the moment also use Method 1 or Method 3 for determining calibration interval on the basis of In-Use time or time period calibration. However, labs are not keeping logs of instrument usage at the moment thus leaving much to the desired. Though these guidelines are at the moment under revision, but we suspect that keeping logs of standard usage may be made essential.

These guidelines in conjunction with additional guidelines laid out by Indian regulator NABL making Unique Lab Reference number for each and every document issued by the lab will make labs operation more difficult and labs not using the software for its operation management are going to spend more time keeping paperwork up-to-date.