Most analyzer specifications clearly indicate the time needed for the analyzer reading to reach 63% (or 90%) of a final reading, in response to a sudden increase in concentration.
These times are based on the response of the analyzer alone, and do not take into account the following that may be present in the complete analyzer system as installed:
Sample Transport Time:
- sample tubing
- scan time
This calls for a more complete response time test: one which measures the time needed to generate an alarm and activate corrective action (shutdown, emergency stop, off-coat, etc.), from a sudden increase in solvent concentration at the very end of the sample probe.