- Radiation detector used to check levels of potentially harmful ionizing particles and rays in the environment and in objects such as particle accelerators, x-ray shielding, and industrial gauges
- Detects ionizing radiation types such as alpha and beta particles, and gamma rays and x-rays
- Dual-scale analog meter with needle-point display of counts per minute (CPM) and milliRoentgen (mR) per hour
- Three selectable operation ranges of X1, X10, and X100 for adjustment when peak mR levels are met
- Red, flashing counter and a beeping noise indicate each ionizing radiation increase event
Radiation Alert MONITOR4 Analog-Based Ionizing Radiation Detector
|Price:||$350.00 ($350.00 / Each) & FREE Shipping. Details|
Specifications for this item
|Brand Name||Radiation Alert|
|Number of Items||1|
|Import Designation||Made in USA|
|Temperature Range||neg 4/131 Degrees Fahrenheit|
The Radiation Alert Monitor 4 is a hand-held radiation detector with an analog display over th... See more product details
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The Radiation Alert Monitor 4 is a hand-held radiation detector with an analog display over three selectable operational ranges for detecting potentially harmful ionizing alpha and beta particles, and gamma and x-ray radiation. This meter has a dual-scale, analog, needle-point display of counts per minute (CPM), and milliRoentgen (mR) per hour. It detects the four main types of ionizing radiation: alpha and beta particles, and gamma rays and x-rays. It has three selectable operational ranges (X1, X10, or X100) to be adjusted when the meter face peaks at the highest mR level.
The Monitor 4 has a red, flashing counter and a beeping noise to indicate each ionizing radiation event. It has a halogen-quenched Geiger Mueller (GM) tube with a thin, mica end window for sensing ionizing radiation. It is used to check radiation levels in the environment and objects, such as particle accelerators, x-ray shielding, and industrial gauges. An audio indicator with an internally mounted beeper can be turned off for silent operation. The Monitor 4 cannot be returned.
|Reading Ranges||0 to 0.5, 0 to 5, or 0 to 50 milliRoentgen (mR) per hour, or 0 to 500, 0 to 5,000, or 0 to 50,000 cycles per minute (CPM).|
|Accuracy||Factory-calibrated by pulse generator, with accuracy + or -15% of reading full-scale, relative to Cesium 137.|
|Energy Sensitivity||1,000 CPM/mR/hr (Cs137).|
|Detection||Alpha down to 2.5 mega (million) electron volts (MeV), with typical detection efficiency at 3.6 MeV at greater than 80%. |
Beta at 50 kilo (thousand) electron volts (keV) with typical 35% detection efficiency.
Beta at 150 kilo (thousand) electron volts (keV) with typical 75% detection efficiency.
Gamma and x-rays down to 10 keV typical.
|Temperature Range||-20 degrees to 55 degrees C (-4 degrees to 131 degrees F) and an internal detector.|
|GM Detector||Halogen-quenched with window thickness of 1.5 to 2.0 mg/cm2. The effective diameter is 0.92 cm/0.36”.|
|Dimensions||Dimensions are 209 mm x 71 mm x 50 mm (8.2” x 2.8” x 1.9”).|
|Weight||178 g (6.3 oz).|
|Output||3.5 mm headphone jack for use with observer software (not included) and Windows-based computers.|
|Normal Background Radiation||Approximately 5 to 20 CPM.|
|Battery||9-V alkaline battery (not included) for approximately 2,000 hours of continuous use in a normal background.|
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?
- Monitor 4 radiation detector
- Carrying case with belt clip
- Instruction manual
- Conformite Europeene (CE) certification
Top Customer Reviews
First, the purchasing. There are two options in the base model, one you can actually assemble yourself and save some cash, the other pre-built and reasonably calibrated. I was lazy and bought it calibrated.
Made in USA of plastic.
It arrived promptly, in perfect condition. It comes with a lightly padded case with a handy clip (for your belt or backpack) sufficient to protect it from 4-foot falls. It works well and the case design allows it to be partially open - holster style - for quick extraction. I lost the case a year ago and really regret that. flashing light, three beep tones (you can turn them off), battery check, and three sensitivity levels (more later).
Basic physical character - It is not tiny, but fits very ergonomically in my hand. weight is 1/2 LB (250 g). Controls are perfectly intuitive, with positive acting slide switches that do not break. It has survived a dozen+ falls without its case, one included bouncing down several flights of rocks. The mica window over the tube has a metal grid which has saved it several times. It is not waterproof. Battery life is VERY long. I have changed the battery twice, ever - but out of paranoia - never once ran out. I'm sure you could keep it switched on for a day or more with a single 9V battery. Extremely robust unit, light enough to hold all day, but not discrete.
Sensitivity is a tradeoff. It has three levels, to 0.5 mR/hour, up to 5 mR/hour, and to 50 mR/hour.Read more ›
First of all, it does count. However, it is not sensitive enough compare to a traditional Geiger counter with a pancake detector.
I have compared side by side that when the traditional one used in the lab gives about 1.5k cpm, this Monitor4 does not show any difference compare to background, even when the detector is about 1-inch to the source.
I am not sure about other application, for serious beta ray detection it does not work well.
It's nice that the meter has a headphone jack, which is a bit easier to interface a computer to than USB. It's also nice that the product specifications for the GM tube are more complete than other Geiger counters I've seen on Amazon. Just be aware that the needle display is not useful unless you happen to be around something that's really radioactive. Also, Geiger counters cannot be returned to Amazon, so you might be stuck with it.
I wish that Amazon gave information about the sensitivity of the GM tubes in each of their Geiger counter products. I would like to find a counter which registers, say, 50 CPM for normal background radiation, using a larger tube window.
Most Recent Customer Reviews
I got the kit version of this as I like building things and this thing feels good in the hand. There had to be a lot of thought behind the design as when you hold it, it just... Read morePublished 12 months ago by Danny H. Newport
BEWARE OF QUALITY.
Unit failed after 1 year and 2 months (just out of the one year warranty) and SE charged me full repair price ($150). It was a bad geiger tube. Read more
Replaced my 1962 CDV meter of the Cold War Era. I have extensive RADEF background, retired and have a low level source... This Instrument detects Alpha, Beta, and Gama radiation. Read morePublished 17 months ago by Capitalone
I have had one of these (non USB) for about 3 years. It has been very reliable and appears to always function properly (including on materials that max out its range). Read morePublished 22 months ago by John A. Luczaj
We go camping in the BLM area in Eastern Arizona. When we saw radiation warning signs by the old uranium mines, I figured we should get this to be sure we are safe. Read morePublished 22 months ago by Gene Chastain
Pro: cheaper than its brother (Inspector). Con: analog meter - have to count the "beeps" to measure CPM/accumulated readings. Read morePublished on August 31, 2013 by J.L.
this is an excellent portable radiation detector and works good on testing well cuttings samples, etc. It has accurate readings too.Published on August 15, 2013 by R. Gilbert
Purchased this at about the time that North Korea was saber rattling. We live in Seattle, which is more or less directly downwind from there, so it's worth having supplies on hand... Read morePublished on June 20, 2013 by M. Culver