What You Should Consider When Choosing A Calibration Service Provider
We recently discussed some common mistakes scientists make when choosing a calibration service provider for their pipettes. As we learned, the choice of a calibration service provider is often made quickly, and without much thought to quality priorities.

People tend to pick a service based on convenience or price, or simply choose to stick with the calibration service they (or others) have used in the past. Though price and convenience are important factors to consider when selecting any service, focusing too much on these aspects of calibration services is a costly mistake. In addition to including unforeseen costs in their pricing structures like parts, repairs or add-ons, many service providers appear to accommodate budget limitations and convenience issues but provide inferior and incomplete services that end up causing additional spend and headache. At the end of the day, if your calibration company does not provide you with reliable pipette measurements down to 0.1ul, the service is worth neither your time nor your money.

So how do you differentiate a high quality calibration service provider from a substandard one? Here are some tips.

1. Determine which standard(s) the service provider actually uses. Most providers will only state that their services are accredited to the ISO 17025 standard, which is an broad calibration industry standard that applies to many industries. However, the ISO 8655 standard, specific to POVA (Piston Operated Volumetric Apparatus) provides a detailed prescription for the calibration of pipette instruments, and significantly increases the chances that pipette measurements are accomplished correctly and accurately. Thus, a provider offering procedures done according to the ISO 8655 standard will leave you with more reliable pipettes than the provider only using the ISO 17025 standard.

2. Check how many balances the service provider uses for calibrations. Distinct balances are required to calibrate pipettes of different volumes with adequate resolution. Using the wrong balance would be similar to a person weighing themselves on a truck scale. Some service providers will use the same balance for pipettes of varying sizes (usually a 4 or 5 place analytical carried into a lab), which prevents superior calibration results. If you notice an on-site service provider entering a lab with only one balance for all your pipettes, the most accurate calibration is simply not possible.

3. Find out if the service provider does calibrations on-site or inside a controlled calibration facility. Proper calibration requires that several environmental factors, including temperature and vibration, be strictly controlled to guarantee the performance of the balances. This is required by the ISO standard to stabilize the balances thereby reducing measurement uncertainty. Though on-site service calibration sounds convenient for scientists, it compromises the quality of the calibration, and is not the only convenient choice. Calibration companies who perform calibrations at their own facilities are likely to have invested in the proper equipment to ensure that the calibration environment is ideally suited to deliver reliable results. Added to this, the best companies also provide next day return or free pipettes to keep while your pipettes are in service.

4. Find out how the service provider conducts the calibration. Some service providers will use unapproved methodology, such as a quick onsite service, which can sometimes be easily identified. One thing to look out for is if the provider conducts a thorough preventative maintenance procedure by opening and cleaning each instrument. Just as cars require routine maintenance to minimize future expense and guarantee reliable performance, these steps are essential for proper function of mechanical pipettes. Some providers will skip them all together! If you notice a provider skip these steps, the provider is not giving you the results you paid for.

Even with these tips in mind, it may be difficult to distinguish between service providers of varying quality. Relying on your Quality Control or Metrologists to initially vet potential calibration service providers may help you narrow down the playing field to qualified candidates. At that point, you can more safely incorporate other important factors, such as cost and convenience, into your evaluation of your options.

TTE is the only provider offering the ISO 8655 standard service complete with a 24 hour turnaround. TTE has no hidden fees and conducts high quality calibration with proper equipment off-site. Learn more about what TTE can do for your lab.