A Proven Solution for Electron Reference Dosimetry

SNC350p is a waterproof, well-guarded, parallel-plate ionization chamber with a design that minimizes perturbation effects as described by Dr. M. Roos et al. (IAEA TRS-381). It is intended for reference, field, and scanning dosimetry of therapeutic electron beams.

Features & Benefits

  • Conforms to the design principles as stated by Dr. Roos
    • Reduces in-scattering perturbation effects
    • Capable of being used with electrons, including low energy beams (< 10MeV) per AAPM’s TG-51 and IAEA’s TRS-398
  • Reference-class dosimeter meeting recognized standards of performance (IEC 60731). May be used to cross calibrate field-class dosimeters
  • Vented to provide air-density correction and eliminate need for radioactive stability check device
  • White chamber body allows easy visualization of the setup relative to the crosshairs and lasers
  • Well Guarded and Fully Guarded
  • Minimal wait time after polarity change
  • No need for secondary water-proofing
  • Triaxial BNC and TNC connector options available
  • Custom fitted and travel-safe storage case

Chamber Comparisons

S3  Chamber Comparisons


Sensitive Volume (cm3): 0.388
Entrance Window (mm): 0.05 Paint
1.00 PMMA
0.02 Carbon
Reference Point (mm): 1. Below Window Surface
Collection Volume Height (mm): 2.0
Collector Diameter (mm): 15.6
Guard Ring Width (mm): 4.1
Polarity Effect: Within 1.000 (±) 0.01
Max Dose Rate for (Gy/s):
≥ 99.5 % Saturation 5.2
≥ 99.0 % Saturation 10.4
Max Dose Per Pulse for (mGy):
≥ 99.5 % Saturation 0.46
≥ 99.0 % Saturation 0.92
Radiation Quality: Photons: Co-60 to 25 MV
Electrons: 5 MeV to 25 MeV
Field Size (mm): Minimum: 40 x 40
Maximum: 400 x 400
S5  Snc350P Diagram