Model 23 mrem Personal Dosimeter

Model 23 mrem personal dosimeter


The Ludlum Model 23 mrem Electronic Personal Dosimeter (EPD) is a compact and lightweight (60 g / 2 oz) pen-type personal dosimeter. It is ideal for the measurement and general monitoring of gamma and X-ray radiation in medical and laboratory environments, as well as any controlled or restricted area where personal radiation monitoring is required or desired. The unit is sensitive to a wide range of energies from 35 keV to 3 MeV. Dose, Dose Equivalent Rate, and alarm values are easily seen on the four-digit LCD screen. An audible alarm is activated if the dose or dose rate exceeds the preset value of the dosimeter. The alarm set points are adjustable from the face of the unit.

The optional Model 23 Series Dosimeter Setting Device and Software Kit (see Options tab below) can be used to configure the dosimeter settings and to quickly take data directly from the dosimeter via infrared communication to a PC. Up to 600 data points can be stored in the dosimeter. Note that all collected data is erased when the dosimeter is turned off, so the data must be transferred before the dosimeter is turned off in order to be recorded.

Warning: This dosimeter will not measure pulsed radiation accurately.

Radiation Detected Gamma and X-ray (35 keV to 3 MeV) Detector Silicon semiconductor Measurement and Display Range
Accumulated Dose: 0.1 mrem to 99.99 rem
Dose Rate*: 0.1 mrem/hr to 99.99 rem/hr
Accumulated dose data is automatically deleted when the Model 23 is switched ‘On’.
Display 4-digit OLED with indicators for dose, dose rate, operating time, and alarm
Accuracy ≤ ±10% (0.01 to 999.9 mSv (1.0 mrem to 99.99 rem), 137Cs)
Energy Response ≤ ±20% (60 keV to 1.5 MeV, 137Cs)
Angular Response ≤ ±20% (Up to ± 60 degree vertical and horizontal, 137Cs)
Dose Rate Linearity* ≤ ±10% (137Cs)
Alarm Volume Approximately 60 dB (at 20 cm)
Data Logging Up to 600 records (optional IR reader required for data transmission to PC)
-10 to 40 °C (14 to 104 °F)
≤ 90% relative humidity (non-condensing)
Power One each coin-type lithium battery (CR2450, P/N 21-8639)
Battery Life 720 hours (without alarm / communication)
Size (H x W x D) 110 x 30 x 12 mm (4.3 x 1.2 x 0.5 in.)
Weight 60 g (2 oz.)

*Note: The instrument indicates rough value for dose rate measurements in low radiation fields, such as less than 1 mSv/h (100 mrem/h), so it should only be used for reference.