White Paper:
SPECTRO Performance Quality System (SPQS)
Optical Emission Spectroscopy (OES) is the most popular and best established technique for the quantitative analysis of metals and alloys. Like most instrumental methods it is a relative technique, where sample measurements are compared to calibration measurements made on standards of known concentration. Any short-term or longterm instability of the measuring system will adversely affect the quality of the results, and instrument suppliers often rely on precision data and results on Certified Reference Materials to indicate the performance of their products. In industries such as aerospace or automotive, accuracy may be of paramount importance.
ASTM E 1009 describes a method for evaluating an OES instrument for the analysis of carbon and low-alloy steels, using specified CRM’s as standards, and includes a way of defining the accuracy of the analysis. Work at SPECTRO Analytical Instruments has used the approach in ASTM E 1009 as the basis for a software-controlled quality control and qualification procedure, the SPECTRO Performance Qualification System (SPQS), which has the potential to be applied to any OES measurement. Calibration and validation specifications can be developed for the user’s specific analyses, using standards chosen to suit the application and imposing accuracy, precision and stability limits agreed between SPECTRO and the customer at the time of ordering. The SPQS can then be applied throughout the life of the OES spectrometer to ensure that this level of performance is maintained, while at the same time generating a secure trail of measurement data for quality audit purposes.
