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Several analyzer types are of sufficiently sound design and manufacture to meet the industry-standard requirements for general purpose gas detection. Many of these also maintain this accuracy under normal conditions for a reasonable period of time following calibration.

It is much less common, however, for the accuracy to be maintained for the following, that are routinely found in industrial processes:

The ability of the analyzer to measure the solvent concentration depends on the delivery of the solvent vapor to the analyzer through a sampling system in which all elements in contact with sample are above the dew points and flash points of all substances in the process. 

Any tendency for leaking in the sample tubing or analyzer is to be avoided, as it will directly affect the accuracy of the reading. For this reason stainless steel or a similarly strong and durable material should be used for sample tubing. 

Leaks can be detected by a "probe injection" of calibration gas. In this method calibration gas is injected close to, or directly at, the very end of the sample tube, and the reading is compared to that reading obtained from the routine calibration method (injection directly at the analyzer). 

Because the analyzer response time is critical, large pre-conditioning filters in the sample line are to be avoided. The delay in a filter can be estimated by dividing the filter volume by the sample flow rate through the filter.