The Radiation Alert Inspector is a hand-held, microprocessor-based radiation detector that detects potentially harmful ionizing alpha and beta particles, and gamma and x-ray radiation, has a four-digit, LCD digital display of millirem (mR) per hour, and function indicators. This radiation detector can detect low levels of the four main types of ionizing alpha and beta particles, and gamma rays and x-rays over automatic operational ranges. It is optimized to detect small changes (low levels) in radiation levels and to have high sensitivity to many common radionuclides.
The Inspector counts ionizing radiation changes, and the unit of measurement is selected and displayed using the mode switch. The display shows various indicators, based on the mode setting, the function performed, and remaining battery power. These include low battery, alert, timer, total mode (to see the number of times a reading should be multiplied by to obtain the correct radiation count), calibration mode, utility menu (timer, calibration, alarm set mode), and units of measurement. It has automatic operational ranges for a variety of radiation detection. A red, flashing counter and a beep noise indicate each ionizing radiation change event. The display updates every three seconds. At low background levels, which are typical in a geographic area, the update is the moving average for the most recent 30-second time period. The time period for the moving average decreases, as radiation levels increase. The radiation detector has a 2”, halogen-quenched, uncompensated Geiger Mueller (GM) tube with a thin, mica end window for sensing ionizing radiation. A radiation symbol on the front label marks the center of the detector. It is used for surveying naturally occurring radioactive material (NORM) contamination, gross wipe counting, contamination inspection of packages, equipment, and people, regulatory inspections, and for low energy radionuclide detection. This detector has a utility menu on the back of the unit. The menu has a three-second response, and switches the detector from mR/hr and counts per minute (CPM) to μSv/hr and counts per second (CPS). It also can reset the calibration factor to 100, adjust calibration, and reset all settings to the default factory setting. The radiation detector has an audio indicator with an internally mounted beeper that can be turned off for silent operation. The Inspector cannot be returned.
Specifications Reading Ranges 0.001 (1&muR) to 100.00 mR/hr, or 0 to 350,000 CPM, or 0.01 to 1000 μSv/hr, 0 to 5,000 CPS, total counts 9,999,000 μSv/hr Calibration Calibrated electronically using a pulse or function generator. Electronic calibration requires a cable with a 2.5 mm plug, with the tip carrying the signal. Accuracy MR/hr + or – typical (NIST), + or -15% maximum 0 to 100, μSv/hr + or – 10% typical (NIST), + or – 15% maximum .01 to 1000, CPM + or – 10% typical (NIST), + or – 15% maximum 0 to 350,000 (referenced to Cs137). It has a factory default calibration reset option that will automatically reset to auto averaging, mR/hr, CPM, and CAL (calibration) 100. Energy Sensitivity 3340 CPM/mR/hr, referenced to Cesium (Cs) 137. Energy sensitivity detects alpha down to 2.0 MeV. It detects beta at 0.16 MeV with typical 25% detection efficiency at 1 MeV. It detects gamma down to 10 keV through the end window. Detection Smallest detectable level for I-125 is 0.02 μCi at contact. It detects gamma and x-rays down to 10 keV typical through the window, and 40 keV minimum through the sidewall. Manual Range Switch Sets at X1, X10, X100, or X1000 to indicate the multiplication factor which determines the complete radiation level. Temperature Range -10 degrees to 50 degrees C (14 degrees to 122 degrees F), and an internal probe. Alert Set Range 0 to 50 mR/hr, and 1 to 160,000 GM Tube A halogen-quenched, uncompensated GM tube with an effective diameter of 1.75”(0.45 mm). Window Thickness 1.4 to 2.0 mg/cm2. Normal Background Radiation Approximately 10 to 20 CPM. The meter will hold at full-scale in fields as high as 100 times the maximum reading for anti-saturation. Dimensions 145 mm x 72 mm x 38 mm (5.7” x 2.8” x 1.5”) Weight 327.4 g (11.55 oz) Output Two 3.5 mm headphone jacks can connect to a computer or datalogger, such as complementary metal-oxide semiconductor (CMOS) or transistor-transistor logic (TTL) device. Sub-mini jack input allows for electronic calibration. The probe port located at the end panel attaches the internal probe. Battery 9-volt alkaline battery for approximately 2,160 hours of operation with continuous use in a normal background. Minimum battery life is 625 hours at 1 mR per hour.
Radiation detectors can detect a broad range of ionizing alpha and beta particles, and gamma and x-rays that may be emitting harmful levels of radiation. They sense ionizing radiation with an enclosed Geiger Mueller (GM) tube to count radiation particles or rays. Alpha and beta particles are measured in counts per minute (CPM) or counts per second (CPS). Gamma rays and x-rays are measured in milliRoentgens (mR) per hour, microSieverts (μSv) per hour, or milliSieverts (mSv) per hour. Alpha particles are positively charged and heavier than beta particles, and have a limited range of approximately 3 to 5 centimeters by air. Alpha particles can be shielded by objects such as paper and unopened skin. High-energy beta particles are electrons, heavier than gamma rays, and can take either a positive or negative charge. Beta particles can be shielded by aluminum or wood. High-frequency (short wavelength) gamma rays are the strongest and lightest rays. Gamma rays are more penetrating than alpha and beta particles. They can be shielded by dense materials such as lead, and large masses of concrete, hardened steel, or water. X-rays are man-made gamma rays, and have essentially the same properties and function. Radiation detectors commonly have either an analog or a digital display. Analog radiation detectors output with a needle-point scale, and digital units generate a numerical LCD digit display. Radiation detectors are commonly used by hobbyists for safety detection and rock inspection, and professionals in the in the nuclear, medical, mining, instructional, and research industries.
SE International manufactures radiation detection products and accessories under the Radiation Alert brand. The company was founded in 1979 and is headquartered in Summertown, TN.
What’s in the Box? Inspector radiation detector Carrying case with belt clip Instruction manual CE certification