The Classic Farmer Type Chamber

SNC600c is a reference class ionization chamber which follows the classic Farmer chamber design and performance, and meets IEC 60731 performance requirements. The white thimble provides high contrast with the cross hairs for easier setup verification.

Features & Benefits

  • Reference class ionization chamber (IEC 60731)
    • Satisfies recommendations of dosimetry protocols
      (e.g. AAPM’s TG-51 and IAEA’s TRS-398)
  • Follows classic Farmer chamber design
    • Compatible with most existing slab phantoms and detector holders
  • Fully guarded, vented, and waterproof
    • Quick setup with no required wait time before measuring
  • White thimble
    • For improved setup and accuracy
    • Crosshairs and lasers easily discerned on thimble
  • Rotational orientation mark
    • Improved accuracy through consistent orientation that calibration laboratory uses

SNC600c Proven Performance

The 600c is designed to offer the superior performance expected in a reference class Farmer type ionization chamber, with the benefit of easier setup thanks to the specially painted white thimble.

SNC600c Comparison

  • 5 cm x 5 cm, 60° Wedge, 1.5 cm depth
  • 40 cm x 30 cm, Open Field, 30 cm depth
  • 30 cm x 30 cm, Open Field, 1.5 cm depth
  • 40 cm x 30 cm, 60° Wedge, 1.5 cm depth
  • 40 cm x 30 cm, 60° Wedge, 10 cm depth
S3 6 Mv 100X100


Active Volume (cm3): 0.6
Active Length (mm): 22.7
Active Diameter (mm): 6.1
Sensitivity (nC/Gy): 20
Wall Material (mm): Paint 0.05
Graphite 0.43
Energy Range: Co-60 - 25 MV
9 MeV - 25 MeV
Electrode (mm): 1.1 diameter aluminum
Vented: To atmosphere through waterproof tubing
Buildup Cap (mm): 4.5
Polarizing Voltage: ±400V Max
Length (m): 1.5
Cable Connector: TNC or BNC
S4  Diagram