At the most basic level calibration is a comparison between measurements. One of the measurements being carried out on a device of known and correct characteristics, known as the "standard" and the other is made in the same way on another device. The stability of your instrument is largely dependant on the application and environment in which it will be used; temperature, harsh conditions and time are all factors to be considered.
All instruments, even those manufactured by the same supplier, may experience performance variance over a period of time. It is also worth considering your adherence to quality systems such as ISO 9001 and ISO 14001; these will require you to manage and maintain systematic, documented evidence of calibration.
Instrument calibration is one of the primary processes used to maintain the accuracy of an instrument. It is the process of configuring an instrument against a known standard to provide a result for a sample within an acceptable range. Eliminating or reducing the factors that cause inaccurate measurements is a fundamental part of instrumentation design.
Although the exact procedure may vary from product to product, the calibration process generally involves using the instrument to test samples of one or more known values called "standards." The results are then used to establish a relationship between the measurement technique used by the instrument and the known values. In essence the process "teaches" the instrument to produce results that are more accurate than those that would otherwise be achieved; the instrument can then provide more accurate results when samples of unknown values are tested in the day to day normal use of the product.
From a practical standpoint, a trade-off must be made between the desired level of product performance and the effort associated with accomplishing the calibration. The instrument will provide the best performance when the intermediate points provided in the manufacturer's performance specifications are used for calibration; the specified process essentially eliminates, or "zeroes out", the inherent instrument error at these points.
The critical question that we need to ask is what are the costs and business risks of not calibrating?
It could mean that you have instruments recording false passes or failures; this immediately impacts on the quality of your service and/or products, and could lead to high levels of rejects or costly rework. It could be that your design teams are spending large amounts of expensive R&D time in resolving issues that are only based on inaccurate measurements.
Are the measurements you are seeing the same as the ones your customer is experiencing; only a traceable calibration can give you the comfort of knowing that your standards are correct. Worse still you could be in a non compliant situation by not adhering to an agreed calibration cycle as laid down by your accreditations or contractual agreements with your customers.
Even though digital instruments are far more stable than their analog predecessors they are not exempt from needing regular calibrations. A regular schedule of calibration will keep your Amplicon instrument in peak condition and working effectively throughout its lifetime.
The simple answer to this question is "when it needs it." From a more practical point, daily or periodical testing can provide an indication of instrument performance, which can then be used to establish a history. If the controls data indicate that instrument performance is stable, or is varying within an acceptable range of values, then there should be no need to recalibrate the instrument. However, if the data indicates a trend toward, or beyond, an acceptable range of limits, or if the instrument displays a short-term obvious shift, then recalibration could be necessary.
The Amplicon calibration services are supported by laboratories holding UKAS accreditation
(ISO 17025) in electrical/electronic and dimensional/mechanical and this is further strengthened
by our ISO9001:2008 certification.
Amplicon calibration provides the following:
Certification traceable to UKAS
5 working day turnaround
Safety testing where applicable
Before and after results including instruments used and uncertainties