Digital Radiation Detectors

SE International is the maker of a fairly comprehensive line of radiation detectors and dosimeters. It is a small, woman-owned manufacturer located in Summertown, TN and is a longstanding vendor to the U.S. Commerce Department. The company has been awarded the Department’s Export Achievement Award for opening new markets abroad. As a measure of SE International’s success, they have quadrupled employee count and doubled plant size since 1984.

A good representative unit is the Digilert 100 Handheld Digital Radiation Alert® Detector, an all-digital unit. The purpose of a radiation detector is to measure potentially harmful ionizing radiation that the human senses cannot detect. The Digilert 100 is sensitive to alpha and beta particles, and gamma and x-rays, that is, the full spectrum of radioactive ionizing radiation. Devices similar to the Digilert 100 were able to detect radioactive Cesium in Tokyo’s water supply following that country’s atomic powerplant crisis. Similar contamination was also found in vegetables such as canola and chrysanthemum greens.

The Digilert 100 has a digital display containing a four-digit LCD with mode indicators. The display is refreshed every 60 seconds. There is a real-time count light that flashes red with each count of detected radioactivity, and a pulsating beeper alarm with three adjustable alert levels. 

You can plug the Digilert 100 into your computer, and/or data logger and download data. Audio output can also be jacked to external devices, such as earpieces, amplifiers, and audio recorders.

The unit is shielded against radioactive saturation, and each reading is accurate to within ten to 15 percent. The heart of the system is a halogen-quenched GM tube containing mica and a window about a third of an inch in diameter. Users can set the onboard alarm to trigger at any alert level.

A range of accessories is available from SE International for the Digilert 100, including two cases: the waterproof case and the Xtreme Boot. You can also purchase related observer software and a stand.