XRF is a non-destructive analytical technique used to determine the elemental composition of materials. The technology is used in mining and exploration for positive material identification in power generation, metal fabrication, inspection and recycling, precious metals and jewelry analysis, consumer safety and regulation, and other industries.
XRF analyzers determine the chemical composition of a sample by measuring the fluorescent (or secondary) X-rays emitted by the sample when excited by a primary X-ray source. Each element present in a sample produces a set of characteristic fluorescent X-rays ("fingerprint") that are unique to that particular element, which is why XRF spectroscopy is a good technique for qualitative and quantitative analysis of material composition.
But precise calibration of the instrument is required to ensure accurate results. Calibration is the process of confirming that a measurement is true by making a measurement against a standard. Calibration is usually performed before the instrument is shipped out of the manufacturer's door. Although portable XRF analyzers are generally very rugged, especially since they are sometimes used in harsh environments, the equipment degrades over time and should be recalibrated periodically.
Therefore, it makes sense to check, adjust, or determine the continued accuracy of an instrument by comparing it to a standard. It is recommended that you follow the manufacturer's recalibration recommendations, taking into account the operating environment, range of use, and instrument history. Companies may even be required to adhere to a calibration plan to ensure compliance with ISO quality documents. For example, ISO/IEC 17025:2005 specifies “general requirements for the competence to perform tests and/or calibrations, including sampling. It covers tests and calibrations performed using standard methods, non-standard methods and laboratory-developed methods.”
Typically, annual recalibration should be done to ensure that measurements are accurate within the specification limits that led you to choose your instrument in the first place.
However, recalibration should only be done by a manufacturer's qualified technician. Never attempt to open the instrument as this may damage or jeopardize the technology and may void the warranty. Manufacturers can also provide calibration certificates to ensure customers have accurately verified your material.
In addition to calibrating instruments, manufacturers should provide hardware checks and maintenance checks to make sure everything is within factory specifications. A trained technician should inspect the case to make sure there are no cracks or damage, make sure the touchscreen is working properly, and test all port connections. Additionally, the brightness of the LCD lighting should be checked, the trigger, navigation and shutter buttons should be working, the camera (if included with the instrument) should be in focus, and the battery should be tested to ensure it is charged.
Do you want to skip calibration and maintenance because you can't do business without an XRF analyzer - you just keep putting it off? Don't. There can be too many negative consequences if the measurement is not within tolerance. If your analyzer is not running at very good performance.
