Evaluating a calibration lab to ensure it meets your needs and requirements is one of the most important steps in finding and choosing a suitable calibration provider. As previously mentioned, a general framework needs to be created for the evaluation. This will make sure that all your needs and requirements are touched on in the questions.
To help you get a better idea of what you should be asking while evaluating a calibration lab, we have created a small guide with example questions below.
QUESTIONS TO ASK REGARDING ACCREDITATION
Asking about a calibration laboratory’s accreditation is extremely important. If a lab is accredited, their scope of accreditation needs to match the requirements you are seeking in order to be a good fit. Good questions to see if a lab meets your needs include:
- What is your scope of accreditation?
- How many parameters does it include?
- What are the parameters specifically, and what are the ranges?
When asking about accreditation and parameters, it is also important to include questions regarding uncertainty ratio measurements. The measurement of uncertainty should be smaller than the specification limits; therefore, you should ask, “What is the best uncertainty measurement you are capable of achieving?”
QUESTIONS TO ASK REGARDING CALIBRATION CAPABILITIES
Knowing a calibration laboratory’s calibration capabilities will also aid in deciding if you should choose them for you calibration needs. Questions to ask regarding calibration capabilities should include:
- What are the levels of calibration you provide?
- What type of documentation is included in those levels?
- Is every specification for every installed option in an instrument tested?
- Do you use procedures and software from original equipment manufacturers?
- Is every specification tested using all operating configurations, ranges and data points?
- If an instrument fails any tests, are adjustments and retesting part of your normal process?
- What adjustment levels can be provided if an instrument fails any performance test?
- Do you do in-house repairs if an instrument cannot be adjusted?
- What is your warranty on repairs if done in-house?
These questions are important to determine if a calibration provider meets the needs of the type of calibration you are seeking, e.g., higher-level calibrations such as ISO/IEC 17025. A quality provider should be able to perform a full suite of OEM tests covering all test points, perform adjustments if needed and/or perform repairs. Notably, calibration providers who send out equipment to OEMs for adjustment and repairs cause a longer turnaround time and can be more costly.
QUESTIONS TO ASK REGARDING CALIBRATION DOCUMENTATION
Proper documentation of calibration services is another important factor to look for when choosing a calibration provider. Documentation of calibration ensures quality of calibration and in many cases guarantees traceability and reliability. Questions to ask regarding documentation include:
- What is included in your measurement reports?
- How do your reports show full coverage of performance testing?
- What is included in your traceability reports?
- Are all instruments listed in report within your scope of accreditation?
- Are all instruments traceable?
These questions will help confirm that the calibration report is detailed and covers all parameters and test points. They will also aid in helping you confirm that required measurement capabilities are traceable to national standards.