1. We begin by clearly defining the purpose of the analyzer. What precisely do we want it to do?
2. Next, determine if a continuous on-line analyzer is needed, or if an intermittent, grab-sample-based laboratory analysis is sufficient.
3. For on-line units, the next step is to determine if the instrument can be removed for calibration or, if automatic, on-line self-calibration is needed. It's also desirable to resolve if the recalibration should be triggered by self-diagnostics, operator initiation or time.

To read the other seven steps, go to the original Control Global article.