CN Column Coordination
Currently all of the aerosol sites have CN counters except IAP (the ARM aircraft).
Column 5 is referred to as CN_control. CN_control is used when the system has been optimized for contamination control. For this configuration, the CN counter (or CPC) is connected to a separate, high-speed inlet.
Column 6 is referred to as CN_ambient. Here the system is configured for ambient sampling. The CN counter takes its sample out of the aerosol sampling line.
The "standard operating procedure" is to put the CN counter in Column 5. There are, of course, exceptions.
This document last modified: December 6, 2005