491Flex™ SD Secondary Dilution Module (SD)

Description

The 491Flex SD Secondary Dilution Module extends the concentration range achievable with a permeation tube calibration system. It is used in series following a 491Flex Base Module and any permeation oven modules. This module introduces an additional, controlled stage of dilution to the primary gas mixture generated by the permeation tubes. By adding a second dilution step, the system can produce final calibration gas standards at significantly lower concentrations than are possible with the primary dilution stage alone. This capability is essential for preparing trace-level calibration standards required for detecting very low concentrations of analytes. The module allows laboratories to cover a wider dynamic range with a single set of permeation tubes, increasing the versatility of the calibration system for applications demanding high sensitivity.