Monitor 4 & 4EC Handheld Radiation Alert® Detector

 

Same Monitor 4. New ergonomic design. The M4 and M4EC are compact, general purpose survey meters capable of detecting alpha, beta, gamma, and x-rays over 3 selectable ranges. A red count light flashes and a beep sounds with each event detected. The Monitor 4EC offers a more linear reading for gamma and x-rays (above 40 keV). Click here for Original Monitor 4. Click here for USB Model.

 

Specifications

Detector
Monitor 4: Halogen-quenched uncompensated GM tube with thin mica window 1.5-2.0 mg/cm2 thick.
Monitor 4EC: Halogen-quenched GM tube, energy compensated sidewall 2mm tin filter. Thin mica window 1.5-2.0 mg/cm2 thick.
Display
Analog Meter holds full scale in fields as high as 100X maximum reading. CPM/mR/hr scale default. Optional SI Meter Scale option available upon request.
Energy Sensitivity
M4: Detects alpha down to 2.5 MeV; typical detection efficiency at 3.6 MeV > 80%. Detects beta at 50 keV with 35% efficiency. Detects beta at 150 keV with 75% efficiency. Detects gamma and x-rays down to 10 keV through the window, 40 keV minimum through the sidewall. Normal background is approximately 10-20 CPM.
M4EC: is the Same as Monitor 4 except the energy response for gamma and x-rays through the detector sidewall is flat within +61% or -26% over the range of 40 keV to 100 keV, and within +35% or -17% over the range of 100 keV to 1.3 MeV.

Gamma Sensitivity:	Operating Range
1000 CPM/mR/hr (referenced to Cs-137) Energy Sensitivity for the 4EC is the Same as Monitor 4 except the energy response for gamma and x-rays through the detector sidewall is flat within +61% or -26% over the range of 40 keV to 100 keV, and within +35% or -17% over the range of 100 keV to 1.3 MeV.	0-.5, 0-5, 0-50 mR/hr 0-500, 0-5,000, 0-50,000 CPM or 0-500 µSv/hr 0-50 mR/hr. Range Switch X1, X10, X100, Battery Check. Accuracy Typically ±15% of reading (referenced to Cs-137)