calibration

Entire books have been written about calibration of test equipment.  In ISO 9001 it is called; 7.6 - control of monitoring and measuring devices.  In many cases the control of such devices is critical to both product specification and contract specification.  In some cases if you don't control such devices carefully and within risk parameters the only way to verify a product is meeting contractual requirements is to conduct destructive testing.  This is not a good protocol or commercial outcome since you cannot sell a product (or service) that has been destroyed in a test to prove it working properly.  But on the flip side, let's not test or calibrate every little piece of equipment in the business just to be on the safe side.  The cost alone of such outsourced services could send you broke or at least dent your gross margins.  Be smart about what you 'need' to calibrate, what you need to monitor and what is just a good guideline to know.

Sometimes, the device is only used as an aid to manufacture, an indicator that things are within defined limits but that their measurements are not used to define final contractual obligations.  A great example of this is the humble viscosity measurement device the 'love cup'.  In the printing game, the viscosity of certain coatings and inks is imperative to usage, colour, texture, etc.  But in nearly all instances, the controlling factor is colour.  So whilst you can get the viscosity right based on the calibrated measurement device, it doesn't mean 'jot' to the customer if it results in the wrong colour.  So why calibrate it.  Well, that becomes a personal decision, a risk decision that has interpretation.  The final outcome cannot be guaranteed when final approval is a subjective as colour! 

So be innovative with your test equipment.  Link calibrations and tests guidelines with risk.  Keep good records of decisions as to why and focus on the core contractual requirements.