CFDC
Continuous Flow Diffusion Chamber

The Continuous Flow Diffusion Chamber (CFDC) is an in situ airborne optical particle counter (OPC). It uses vertical flow through two chambers with different wall temperatures to grow ice particles within the OPC at the bottom of the instrument, thereby determining the particle size distribution. If conditions are stable, the CFDC can also measure flow rate, temperature, and humidity. It measures the size distribution of aerosol particles from 0.4 to 20 mm. The device counts particles every 0.2 seconds and records particle spectra every 10 seconds.