Since its inception in 1986, IMI has been at the forefront of the design and development of radiation monitors. Following Three Mile Island, IMI was involved in the creation of a model pilot radiation monitoring system for communities around nuclear facilities. That tradition was continued and expanded upon with the evolution of their pioneering PC-based real time radiological monitoring network installed around the Seabrook Station nuclear plant for the local community with support from the Commonwealth of Massachusetts. Today, that same creativity and passion for a healthy planet are incorporated in the Hawk Environmental Radiation Monitoring System capable of continuous outdoor monitoring of alpha, beta and gamma radiation.
IMI also manufactures a wide variety of pocket sized, low power digital surface contamination detectors and radiation monitors such as the Inspector Alert and Radalert 100, respectively. In addition, IMI has a low cost line of radiation detector instruments suitable for educational purposes. Finally, the newly released Onyx Radiation Monitor represents the most modern styled and sophisticated radiation detector in the market today.
The Inspector Alert™ measures alpha, beta, gamma and x-radiation using a 2-inch “pancake” GM detector with high sensitivity to common beta and alpha sources. The easy-to-read digital display shows readings in your choice of µSv/hr, mR/hr, CPM, or CPS. The Total/Timer feature allows timed readings from one minute to 40 hours for precise measurement of low level contamination. An audible alert sounds when the radiation reaches a user-adjustable level.
- Quickly alerts first responders to the presence of harmful levels of nuclear radiation
- Improves safety in the laboratory and in the field
- Automatically compensates for GM tube dead time
- Will not jam in high radiation fields
- Meets CE certification requirements for Europe
The Radalert 100™ is a general purpose geiger counter that measures alpha, beta, gamma, and X-radiation. Exciting new features of the Radalert 100™ (which is the upgraded version of the popular Radalert 50™), include a three-second update and a utility menu that allows you to change the default settings for several operating parameters. Its digital liquid crystal display (LCD) shows the current radiation level in your choice of milliroentgens per hour from .001 to 110 or counts per minute (cpm) from 0 to 350,000. When SI units are selected, the LCD shows readings in microsieverts per hour from .01 to 1100 or counts per second (cps) from 0 to 3,500. This instrument also offers an accumulated total and timer function, up to 9,999,000 counts and 40 hours.
The CRM-100™ is a general purpose geiger counter that measures alpha, beta, gamma, and x-radiation. It is intended for personal safety and educational purposes. Like the popular Radalert 100™, the CRM-100™ features a 3-second update on its digital liquid crystal display (LCD). The LCD shows the current radiation level in your choice of milliroentgens per hour from .001 to 110 or counts per minute (cpm) from 0 to 350,000. When SI units are selected, the LCD shows readings in microsieverts per hour from .01 to 1100 or counts per second (cps) from 0 to 3,500. This instrument also offers an accumulated total and timer function, up to 9,999,000 counts and 40 hours. A red LED blinks and a beeper chirps with each count (the chirp can be muted).
Product Pricefrom $85.00
The GeigerGraph software works with the Radalert 100™ and the Inspector Alert™; as well as our discontinued models, the Inspector™, Radalert 50™, and The Geiger™. The GeigerGraph receives each pulse or count from the instrument through the data cable, and displays and graphs the Current reading, an Average, and Minimum and Maximum counts per minute (CPM) over the test period.
You can order the GeigerGraph software as an option when you buy the Radalert 100™ or the Inspector Alert™.
Download free demo (This is a zip file; you need to unzip it to run it.)
The GeigerGraph software is useful for continuous monitoring of environmental radiation. It alerts you to any elevated levels relative to your typical background count. The software gives an audible and visual alert whenever the CPM exceed a user-determined level. For example, in the picture above, the radiation level increases to above the user-set Alert Level of 100 CPM halfway through the test period, and the software issues a visual alert.
Both versions require the minimum operating system of MS Windows 98, ME, NT, XP, Vista, or 7; a USB connection cable is included with each order. An optional RS-232 cable is available upon request.
Living With Radiation: The First Hundred Years
In the century since radioactivity was discovered, radioactive substances have been used extensively for a number of applications. Especially in the early part of the 20th century, and to a lesser extent today, a number of commonly available products have been radioactive. These include:
- luminous watch dials (radium and tritium)
- orange ceramicware (notably Fiestaware from the 40s and 50s; uranium oxide)
- smoke detectors (americium 241; in current use)
- gas camping lantern mantles (thorium; some manufacturers no longer use this)
- camera lenses (thorium)
- static eliminators for film and records (polonium 210)
- welding rods and arc lamps (thorium)
- vacuum tubes (thorium was used to increase electron emission)
A fascinating look at the proliferation of uses of radioactive materials in the last century can be found in the book “Living with Radiation: The First Hundred Years” by Paul Frame and William Kolb. It tells the story of the use of radioactive materials in consumer and commercial products in the century since radioactivity was discovered.
Second edition; copyright William M. Kolb and Paul Frame, 2000; 256 pages, numerous photographs.
The Hawk EMS® – Environmental Monitoring System is a wall or tripod-mounted radiation monitoring and alarm system designed for use with the Hawk Radius® radiation probe (sold separately). The Hawk EMS® features two displays that show the radiation levels measured by each of the probe’s two detectors: the “pancake-style” Geiger-Müller tube — which measures alpha (if configured for it), beta, gamma, and x-radiation — and the energy-compensated gamma tube. The probe can be mounted nearby or set up in a location up to several thousand feet away, indoors or outdoors.
The Hawk EMS® is targeted for applications requiring continuous monitoring and alarm capability for radiation levels exceeding a user-defined maximum. Typical applications include HVAC building air intake monitoring, hospital environments, medical imaging facilities, scrap metal processing, scientific research facilities, building entry points, and warehouses. The system is designed to be low cost and serve as a “tripwire” to warn responsible personnel of potential hazard. As such, it does not provide isotope identification or extreme sensitivity. It can easily detect a small increase from the background radiation level within 30 seconds, and provide an indication if the source is purely gamma/x-ray, or whether it also contains beta and optionally alpha particles.
The Hawk EMS® can be used as an area monitor, environmental monitor, portal monitor, entrance monitor, building monitor and perimeter monitor. It optionally can be used to shut down air intakes on a building with an external adapter that samples air from the air intakes.
- User settable ALERT functions provide audible and visual warnings within seconds after a change in radiation level. An optional output can control external devices when an alarm occurs.
- The attractive wall mount enclosure can blend into an office environment, but is suitable for industrial and security applications. A secured access panel controls all functions and is available with tamper resistant fasteners. Cables can be routed through the back wall, or through the bottom panel.
- Control Panel allows setting the alert level for each detector, power switch, mute alarm function, and access to interface cables.
The Hawk Radius® radiation probe is a sensor for monitoring ambient levels of ionizing radiation as part of an environmental monitoring and security system. In its standard configuration, the probe detects beta, gamma, and x-radiation with one channel and energy compensated gamma with a second channel; it can be configured to detect alpha radiation as well. This dual channel configuration is the preferred method for simple alarms, providing information to determine what type of source is involved. The Hawk Radius® is intended to operate in conjunction with a data logger, the Iospectra® Hawk, or a computer running the Hawk Radius® software, which can be configured to provide a user-defined alarm function. Proper installation, use, and maintenance of the Hawk Radius® probe are essential to ensure safe and reliable data collection.
Applications include homeland security, community protection, public health & safety, scientific research, and education. Environments commonly monitored for radiation may include border security stations, shipping & receiving depots, ports & docks, customs facilities, medical facilities, nuclear power plants, and public event venues.
Detection of Radiation
Each ionizing event detected by the probe transmits a pulse to the data logger or computer, and the relative radiation level is measured typically in counts per minute. It is normal for a background count to be present due to naturally occurring radiation from both terrestrial and celestial sources. As a general guideline, a background radiation level of 25 to 100 counts per minute may be considered typical, depending on your location and local environmental factors. In the presence of unusual ionizing activity, the count rate will increase.
At very high count rates (above 20,000 CPM), dead-time correction may need to be applied to the program in your data logger or computer. Dead time is 136 μs. For most applications, where the probe is used to detect unusual ionizing activity at low levels of radiation, dead-time compensation will not be a concern.