The Farmer type chamber FC23-C is an air cavity ionization chamber, vented through a waterproof silicon sleeve. It is waterproof and fully guarded.
FC23-C is PTB approved (15.101 / 97.02).
The watertight chamber consists of conducting plastic outer and inner electrodes, supported by a thin aluminum stem. The stem is connected to a 1.40-m cable shielded by a watertight silicon sleeve that allows for air ventilation.
The chamber is designed preferably for the energy ranges of photons and electrons at medical accelerators. It can also be employed in X-ray beams with generating potentials from 70 kV to 280 kV and for gamma radiation of 137Cs and 60Co. The energy range of proton beams with available chamber factors is between 50 and 250 MeV.
Figure 1. FC23-C chamber and its build-up / alignment cap.