AQA — ensuring reliable analyses 


Accurate and precise measurement values are absolutely essential in analysis. However, there are a large number of factors that can affect both accuracy and precision. Errors are a real inconvenience when they are spotted too late. Analytical quality assurance makes sure that your analysis results are both reliable and reproducible.

When an electrician installs a light switch, he can turn the light on to check his work. Unfortunately, checking for incorrect or imprecise results is not so black and white in an analytical laboratory. Analytical quality assurance, or AQA for short, brings light into this grey area.

The security offered by our ADDISTA system
It could be a faulty instrument, a contaminated reagent or incorrect sample conditioning. There are many causes of errors in an analytical laboratory. Herein lies the problem: they are often not as easy to spot as, say, a faulty light switch. Occasionally, they can render a series of measurements taken over many months unusable. Make sure this doesn't happen: use the ADDISTA system as a quick way of checking your equipment and methods.

The ADDISTA pack contains:

  • 85 millilitres of standard solution or spiked solution for up to eight different parameters
  • Two round robin test solutions of different concentrations. Participation in the HACH LANGE round robin test is free of charge

The standard solution is used to check the accuracy of analyses. The target value specified on the packaging must be reached within the confidence interval; if this is the case, you can be rest assured you have a functioning measurement system and can go on to analyse your actual samples.

Round robin test with external, independent quality assurance
Another quality measure available is the round robin test. The samples required for this test also form part of the ADDISTA pack. Simply measure the concentration of the relevant parameter as per the instructions and send us your results. Once the results have been evaluated, you will receive information on the accuracy and precision of your analysis. Many authorities accept this document as part of the external quality assurance process.

Performed on a regular basis, the AQA measures described here will render your measurement results produced in the laboratory more meaningful. Now that's a real boost for your confidence.