The R4 is a lightweight and robust device for radiation measurement in the laboratory or in the field; offers maximum performance.
The R4 is a small, handheld, digital radiation meter that offers excellent sensitivity to low activity alpha, beta, gamma and x-rays and allows to calculate activity in Bq and DPM for common isotopes.
It has a backlit digital display, a red count light, and a beep sound whenever a count is detected.
Other features include selectable alert levels, an adjustable timer and optional wipe test plate.
Internal memory and free Observer USB Software allow you to download your data for easy reporting, set computer alarms and download your collected data from internal memory.
Working Range
mR/h - .001 (1µR) to 100 CPM - 0 to 350,000
µSv/h - .01 to 1000 CPS - 0 to 5000
Total / Timer - 1 - 9,999,000 numbers
Accuracy (Cs137)
mR/h ±10% typical (NIST), ±15% max - 0 to 100
µSv/hr ±10% typical (NIST), ±15% max. - 01-1000
CPM ±10% typical (NIST), ±15% max - 0 to 350,000
Energy Sensitivity
Detects alpha beam up to 2 MeV.
Detects beta beam up to 0.16 MeV; Typical detection efficiency at 1 MeV is about 25%. Detects gamma ray up to 10 KeV from the end window.
3340 CPM/mR/hr (Cs137).
The smallest detectable level for I125 is 0.02 µCi at contact.
Built-in Efficiency
5 Sulfur (S35), 90 Strontium (Sr/y90), 137 Cesium (Cs137),
32 Phosphorus (P32), 14 Carbon (C14), 131 Iodine (I131),
60 Cobalt (Co60) and Alpha
Warning Setting Range
mR/hr 0.001 - 50 and CPM 1-160,000.
1d @ 70db
Power source: 9 volt alkaline battery, up to 2000 hours of operation.
Temperature range: -10° to 50°C (14° to 122°F)
Weight: 275 g (9.7 oz)
Dimensions: 178 x 75 x 41 mm