These guard columns and transfer lines are designed to prevent water vapor from reaching the surface, preventing aggressive hydrolysis.

• Extend analytical column lifetime by preventing degradation from harsh 'steam-cleaning' water injections
• Maximum temperature: 325 °C
• 30-meter lengths are banded in 5-meter sections
• Diameters greater than 0.10 mm are tested with the Grob test mix to ensure high inertness

When transfer lines from purge-and-trap systems, air monitoring equipment, or other instruments carry condensed water vapor, deactivated column tubing quickly becomes active because of the creation of free silanol groups.

With Hydroguard® deactivated tubing, a unique deactivation chemistry creates a high-density surface that is not readily attacked by aggressive hydrolysis. The high-density surface coverage of the Hydroguard® deactivation layer effectively prevents water vapor from reaching the surface beneath. Use Hydroguard® tubing for connecting GCs to these devices:
Headspace analyzers
Air analysis equipment and concentrator units
Purge-and-trap systems

These silanol groups adsorb active oxygenated compounds, such as alcohols and diols.