Simple and Reliable Daily QA

A therapy beam constancy meter intended for simple radiation output checks.

The CHECKMATE 2 Advantage

  • Simple to use
  • Cost effective solution
  • Automatic temperature and pressure correction
  • Accurate measurement of:
    • CAX output
    • Repeatability
    • Monitor chamber linearity
  • Built-in rechargeable batteries:
    • Safely keep cables off the treatment floor position advance
  • Hardware
  • Single vented ionization chamber at a depth of 1.0 g/cm2
  • Precision alignment template with light field markings at 10 x 10 cm and 20 x 20 cm
  • Large, easy to read display:
    • Easily viewed at the control station bunker monitor
  • User calibration:
    • Stores up to 15 calibration values
    • Automatic memory


  1. Turn on the power switch.
  2. Place CHECKMATE 2 on the treatment couch and align the crosshairs and the light field to the instrument template.
  3. Expose CHECKMATE 2 to the beam.
  4. Read the measured dose on the numeric display on the end of the instrument.

The numeric dose value displayed indicates the percentage of the stored calibration value. The displayed value can be viewed on the bunker monitor or directly by entering the vault.

Checkmate  Process1


Checkmate  Features
Detector Type: Vented Ion Chamber
Detector Quantity: 1 - CAX
Detector Volume: 0.6 cm3
Field Size: 20 x 20 cm
Inherent Buildup: 1.0 ± 0.1 g/cm2
Inherent Backscatter: PMMA 2.3 cm
Radiation Measured: Electrons, 5 MeV to 25 MeV, Photons, Co-60 to 25 MV
Beam Limits: Max. dose per pulse: 3.65 cGy, Max. avg. dose rate: 3410 cGy/min
Short-Term Reproducibility: 0.5%
Long-Term Reproducibility: 0.5%/year
Temperature / Pressure Correction: Automatic
Calibration Factor Memory Positions: 15
Display Units: Percent of calibration value; set by user
Display Range: 0.1% to 999.9%
Dimensions / Weight: 25.5 x 40.0 x 5.5 cm/4.9 kg
Battery Operation: 8 hours minimum
Number Of Connection Cables: Power charger for internal batteries