The main difference between the two conductometric types is the direct detector's susceptibility to interferences.

Conductometric Technologies

Conductometric TOC detectors measure CO2 in the liquid phase. The two conductometric type detectors are Direct Conductometric and Membrane (or Selective) Conductometric. The two conductometric-type detectors have stable calibration and high sensitivity. The primary difference between the two conductometric types is that the direct detector is susceptible to interference from ionic contamination, acids, bases, and halogenated organics.

In the membrane-based conductometric method, the membrane is a protective barrier to interfering ions, enabling the analysis of CO2 only. The result is a more accurate TOC reading. GE Analytical Instruments (formerly Ionics/Sievers Instruments) developed and patented the Sievers Membrane Conductometric Detection method (also known as "Selective Membrane Conductivity") for measuring TOC. Click here to learn more about the Sievers technology.

Technology Animations

View our technology animations (see Quick Links to your right) to better understand the differences between Direct Conductivity and the Membrane Conductometric Detection methods.