Microchambers
Microchambers were developed specifically for the assessment of radiation fields encountered in stereotactic radiosurgery. Their excellent spatial resolution and waterproof
construction also make them well suited for other radiation beam measurements, including beam calibrations.
Outwardly, the Exradin® A14 is identical to the Exradin® A1, but with a sensitive volume 5.5 times smaller, the A1 and A14 feature a true cylindrical chamber design, whereas, the Exradin® A14P features a true planar design with a 1.5 mm collector diameter and collector gap of 1 mm.
The chamber wall, collector and guard are made entirely of C552 Shonka conducting plastic, simulating air. C552 is an air-equivalent formulation, which makes it ideally suited to the measurement of exposure. C552 consists of polyvinylidene fluoride, carbon black and silica. Density is 1.76 g/cm3.
Electrical resistivity is on the order of 0.03 ohm-meter. Tissue-equivalent versions of these chambers are also available.