Calibration is the method of setting a measuring device by adjusting it with a known accuracy, also called as ‘standard’. This technique determines if an instrument or device is producing accurate and measurable results within the specified limits as compared to those produced by a traceable standard over an appropriate range of measurements.
With calibration, you achieve 2 main objectives:
a) Checking the accuracy of an instrument
b) Determining the traceability of the measurement
If the equipment and instruments you use are not regularly calibrated, you risk reducing their consistency, quality and safety.
Why is Calibration Necessary
Even if the instruments produce accurate measurements today, you can’t be assured of accurate measurements over a period of time. You will observe a ‘drift’ in the readings which is a shift from the specified limits. Factors such as overuse, environmental and external factors such as electrical and mechanical shocks, and wear and tear causes a drift. Calibration helps in minimizing these uncertainties and eliminating drift right at the beginning instead of letting it become significant. Calibration helps in controlling and quantifying uncertainties and errors to an acceptable level. It also helps in improving the accuracy of the measuring device, thus improving the quality of the end product. With calibration you can be confident in your results which you can record, control and monitor.
How Frequently Should You Calibrate
There is no correct answer to ‘how frequently should you calibrate?’. Different instruments have different calibration needs. If you don’t calibrate frequently, the measurements will suffer; at the same time calibrating too frequently isn’t ideal as it is expensive. Let us look at 7 different factors that help in determining the calibration frequency.
1. Consider the criticality of the measurement location. You must calibrate more critical locations more frequently as compared to the less critical locations.
2. Keep a check on the operating conditions and workload of the instruments. Those taking a lot of workload or operating in tough conditions must be calibrated more frequently.
3. Check the frequency of calibration the equipment required in the past. The stability history of the instrument will give you a good idea on how to plan and schedule calibration.
4. Calibrate an instrument before you have to take extremely important measurements.
5. If sudden unforeseen events, such as electric fault, extreme weather conditions or damage to the instruments due to an impact or falls occur, conduct a calibration process immediately.
6. If you think that there are any discrepancies in the final product or if there is a visible shift from the acceptable criteria, it means you have to calibrate that instrument. Small variations are normal but if it crosses the acceptable limit, calibrate immediately.
7. Adhere to the timelines and frequencies suggested by the instrument manufacturer.
Risks of Not Calibrating Frequently
You couldn’t be more wrong if you think that it won’t matter if you skip one calibration schedule or that frequent calibration isn’t necessary. If you do not calibrate regularly, you may face one of following 4 issues:
1. You will see numerous discrepancies and faulty readings in the final product, which will compromise the overall quality of the product.
2. In every pharmaceutical product, safety is absolutely essential. If the product isn’t safe to use or lies low on quality, you can put thousands of lives at risk. Using non-calibrated instruments will almost always cause wrong measurements of raw materials while producing medicines or sensitive instruments such as thermometers, causing safety threats to the consumers.
3. When you use non-calibrated instruments, your end product will show discrepancies. This would mean that you will have to shut down the concerned processes and conduct a complete recalibration, increasing downtime. When you calibrate equipment regularly, the downtime will be minimized. Furthermore, it will also help you identify warning signs before they cause any significant damage to the end product.
4. If the consumers receive subpar medical products, they will ask for a refund or even press legal charges against your company due to the damage caused to them. You won’t just lose money but also put your reputation at risk. You may even face product recall, which is an expensive affair. The risk of litigation increases significantly if you use do not calibrate your equipment frequently.
What are the Instrument Calibration Regulations
There are numerous instrument calibration requirements that pharmaceutical companies must adhere to. In Europe, industry calibration requirements fall under the jurisdiction of the EMEA (European Medicines Agency), as well as local legislation, and in the US, the FDA oversees it. You must keep your calibration records up to date and ensure that you execute instrument calibration to the exact standards of written and approved procedures. Keep a master history record of every instrument in the plant. All the instruments must have a unique ID and all the product, process and safety instruments must be physically tagged and color-coded.
Set a calibration period and error limits for each instrument, which should tally with national and international standards. Ensure that they are more accurate than the required accuracy of the equipment being calibrated. Train your team properly and make sure they are competent to execute various calibration tasks and provide documented evidence of this.