When run on a Waters Acquity H-class QSM, the Agilent Enterprise Edition OQ LC Test Suite Gradient Composition Linearity test frequently demonstrates a slight inflection at the 100% to 95% transition. As a result, for some systems the 95% gradient linearity step may fail with a value less than the Agilent Recommended limit of 0.99900. The Acquity QSM is equipped with an electronically controlled inlet check valve. Similar behavior has been observed in other Liquid Chromatographic systems with electronically controlled inlet check valves, and adjustments made to the Agilent Recommended test limit.
It was determined after reviewing the results from a number of representative systems that a more appropriate value for the 95% gradient linearity step is 0.99500.
Operational Qualification is predicated on operational conditions representative of the regular use of a system across the complete duration of their lifecycle. It is ultimately the customer's PQ that proves the suitability of the instrument to the customer's application.