12 best radiation monitors

Product description

Gmc-500+ (Plus) is a new generation Geiger counter from GQ electronics. It can log the data to Server via Wireless Wi-Fi connection and internal memory at same time. build-in Wi-Fi ready, stay connected with Geiger counter world map free Online history unlimited data storage and Geiger counter world map service. Get the reading from anywhere of the world. Software Submit the data every minute. It is time to get this monitoring instrument. real-time testing evaluation, scientific testing on sample like: building material, hospital radiation therapy monitoring for cancer, food, water, indoor/outdoor-ray, and more.. real-time graphic, text and large Font mode(record radiation data and play it back later) this is a ready to go set. Everything included. No any adjustment needed. place it anywhere and then read the data.

User questions & answers

Question:	How do you charge this unit? It came only with USB cable
Answer:	The GMC-500+ can be charged by any standard USB power adapter, even a computer USB port. You can just connect the USB cable to any USB port.
Question:	Does it have GPS inside
Answer:	No. Only GMC-510, GMC-520 has GPS feature.
Question:	Will this detect if there is radiation in seafood that's in it's package, like in the supermarket or if seafood in a restaurant is safe to eat
Answer:	No, well only if it is been recently radiated. The problem with food radiation testing is it has to be tested in carbon form....burnt to ashes, then tested! Water content masks detection. So not useful for food
Question:	Will this detect radiation from a smart house? Phones, lights. Doorbells, routers.smoke detectors etc
Answer:	No. This device detects only short wave radiation (gamma rays, x-rays and beta radiation). You will need an electromagnetic radiation detector that detects longer waves like ELF's (extremely low frequency waves), radio waves and microwaves.

Product features

New model from GQ Electronics LLC, Seattle, USA

This GQ GMC-500+ Geiger counter is a portable nuclear radiation detector. It detects Beta, Gamma, X-ray radiation and can be used as continuous radiation monitor or used as a personal dosimeter to track the radiation received

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Nuclear radiation is invisible but threatening to human health, environmental safety. For example, if receive 100 mSv radiation, the cancer risk increases.

This meter detects and visualizes the radiation in real time, give you a peace of mind. It can record the historical data for future analysis.

The thoughtful design provides easy-to-use basic features as well as advanced features for users want to explore more

Stand Alone Detection Mode

• Only need ready-to-go main unit
• Carry the main unit and detect the potential radiation around you any time
• Can be used as personal accumulative dosimeter (user time reset able)

Continuous Monitoring Mode

• Use with PC to continuously monitor the radiation anywhere, any time frame
• The main unit is designed to place, hang, hold anywhere
• Seattle, WA service center
• Online support forum community
• Phone & email support from Seattle

Basic Features

• Fast reading in seconds after turn on
• Accurate & real-time data
• Display CPM,uSv/h, mR/h in one screen
• Real time Recording
• Data record first, playback later
• Real time clock
• LED Visual & Audio Alert
• Large Text,Text,Graphic Display

Main Unit Build

• Small 5 x 3 x1
• Light & portable
• Two Geiger sensors
• Rechargeable battery
• Large LCD Graphic UI
• Adjustable Back lit
• Advanced CPU on-board
• Build-in internal flash memory
• Build-in WiFi module
• On-board speaker & Gyroscope

Advance Features

• Independent calibration factors
• Bar & line graph
• USB data port
• Data logging
• Submit data to any server in the world automatically
• Open Protocol

Data Viewer Software Converts Data to Universal Format

• PC GMC data viewer software is included free for downloading the history data. And the data can be saved as standard .CSV format file.

WiFi Data Logging to server for sharing the data

• Open Protocol for easy integration to other application system
• WiFi data logging to GMCmap server with free unlimited data storage.

iPhone APP provide easy access to data

• iPhone APP facilitated use with cellphone

Specification

• Radiation Detection: Beta, Gamma and X-Ray .
• Detection Dose Range: 0 ~ 42500uSv/h
• Detection CPM Range: 0 ~ 982980 CPM
• Detectable Energy Range: 0.1~3.0 MeV
• Own Background: 0,2 Pulses/s
• Working Voltage: 3.2-4.0V
• LCD Display: Dot matrix with back light
• Working power: 0.045W - 0.2W
• Power: 3.6V/3.7V battery / USB power

Applications

This unit can be used to detect/monitor/measure low dose background environment either indoor or outdoor.

• Alert you once big incident happens: like dirty bomb, Fukushima, Chernobyl.
• Nuke plant environment radioactive plume like Fukushima
• Space radiation, air industrial and on airplane.
• Real-time testing evaluation and scientific testing on samples

Fruit and imported food radiation testing

The GMC-500 Plus can detect the radiation if the fruit has been radioactive contaminated.

Carry the unit with you to test air, food, water and personal environment

Radioiodine (I -131) Therapy

The GMC-500 Plus can be used to monitor the radiation level during the treatment and keep the family member at the safe distance. It can be used to monitor if any one is under I-131 treatment around you.

Use the GMC-500 Plus for Hospital Radiation Therapy Monitoring & Radio iodine Treatment Monitoring

Applications

This unit can be used to detect/monitor/measure low dose background environment either indoor or outdoor.

• Lab research, oil field, and material testing
• Stone collection, marble counter-top, building material and antique collection
• Real-time testing evaluation, scientific testing on samples
• Measuring on Antique radiation level like Vintage Fiesta Dinning Ware and others

Product description

GQ gmc-300e Plus is a newer GMC300EPlus Fulfill of gmc-300 Series Geiger counter. Compared to the previous model, gmc-300e Plus improved overall quality. It installed a high contrast black/white LCD module, added a front LED indicator/an audio data port. The audio data port can be directly connected to any third party device application as data input, such as iPad. It is designed to be a portable/convenient device. It has built in audible and visual signals for the level of radiation detected. It can be used for nuclear radiation detection and monitoring both indoor and outdoor, as well as in other similar environments. It features automatic data recording. It can continually monitor the radiation and log the data each second into internal memory. When connected to a PC, software can download the radiation history data to the computer and the user is able to analyze those data later. the device is equipped with an USB port, utilized for communication and external power supply/charging of the internal rechargeable battery. The GQ gmc-300e Plus internal rechargeable battery can be charged via a wall adapter or via a car charger through the car cigarette lighter. By using the adapters, continuous data monitoring is possible. Using either power adapter you will not have to worry about the batteries charge condition or any data loss. The main board also has a real time clock on board for time related data logging purposes. The USB port communicates with the GQ gmc-300 soft Geiger counter software and the GQ Geiger counter data viewer software. the GQ gmc-300 soft Geiger counter software's appearance is an exact copy of the gmc-300 hardware human interface. You can download it for free and Explore the gmc-300 user interface before you purchase the real hardware. the GQ Geiger counter data viewer software can download the time stamped radiation (history) data from the unit and save it on a computer for future References analysis.

User questions & answers

Question:	Will this measure the radiation level present in gemstones
Answer:	Not all gemstones emit high enough levels of radiation that can be discerned above ambient levels of radiation and it depends on the actual level of radiation the stone emits. Stones that have been exposed to radiation to change their color will probably not register. I have some uranium marbles that are not detected by this counter. My wife was subjected to a PET scan, last year and read 790 CPM from a distance of 6 feet.
Question:	can I use this to measure Fukushima radiation in seafood
Answer:	I've read articles regarding radiation in seafood indicating the levels you read may be may be misleading. The GMC-300 will measure this radiation. Here in Northern Indiana the ambient level is normally 30 - 40 CPM. As shown in the video, levels in sea life can be higher. http://www.opb.org/news/article/scientists-say-stop-worrying-about-fukushima-radio/ Rick
Question:	I'm a novice wanting to check for radiation levels. Is this device easy to understand? What can I use this for to measure for radiation
Answer:	The GMC-300 is easy to use and low priced as an entry level radiation detector. I use mine to monitor background levels of radiation as I have yet to find an highly active source. Here in central BC, Canada I get 14 to 22 cpm, with a high of 30 cpm. It appears to decrease after a rain fall. The only thing missing with the GMC-300 is a radiation standard but I can understand why.
Question:	Would this device be able to tell if there was leftover radiation from a nuclear blast or contamination? Or radiation from dirty bombs
Answer:	I’m a radiation protection technician. If this device works the way that it says it does then it would still not detect alpha or neutron radiation. If you suspect something making into your food or water then I would be most concerned with Alpha particles and this doesn’t measure those. You shouldn’t have to worry about neutron radiation though and unless you’re using it to measure something you’re ingesting then alpha radiation really isn’t an issue. Geiger- Mueller counter can detect beta and gamma/X-ray radiation. I’d be interested to see how they measure Beta since you really need a gas chamber to measure it accurately. I would be most worried about beta and gamma radiation if you’re talking about an area that may have had nuclear weapons detonates years ago. This claims it can measure for those. If it can it would be a good device to determine if your surroundings are still giving off radiation.

Product features

GQ GMC-300E Plus Geiger Counter Nuclear Radiation monitor Data Logger

This popular Geiger Counter is designed and developed by GQ Electronics(USA). It is a portable and convenient device. It includes all necessary features for nuclear radiation detection. It features automatic data recording. It can continually monitor the radiation and log the data each second into internal memory, and then play back later. It is a useful and easy to use device.

Easy to Read

Large Font mode can be selected from CPM, uSv/h and mR/h anytime.

Easy to Understand

Graphic mode graphs the last 60 seconds radiation changes in real time.

Easy to Get

Text mode provides all information you needed in one screen per selected or predefined.

Easy to Configure

Menu mode allow user to easily set the configuration of the device.

Stand alone mode

Most easy way to work with. Hand held and easy to carry around.

Work with a PC

Download the history data from a PC. Real time monitoring on a PC.

Data collection

Comes with free software for data collection and analyze.

Log data to server

Log the unlimited data to GMCmap server in real time.

Specification

• Radiation detection: Beta, Gamma and X-Ray .
• Sensitivity to Gamma Radiation: 0.1~1 MeV
• Own Background: 0,2 Pulses/s
• Working Voltage: 3.7-5V
• LCD Display: Dot matrix with back light
• Working power: 0.045W - 0.2W
• Power: 3.7V Li-on 14500 rechargeable battery / USB power

GQ GMC300EPlus Fulfill Digital Nuclear Radiation Detector Monitor Meter

The handheld device can be easily carried to fields for close-up radiation monitoring or testing.

Fruit and imported food radiation testing

The device can detect the radiation to determine if the fruit and imported food have been radioactive contaminated. Avoiding contaminated food is crucial to our health.

Seafood radiation testing

Many seafood may be contaminated with nuclear radiation materials. It is useful and safe to check the seafood before we consume it.

Radioiodine (I - 131) Therapy

The GMC-300E Plus can be used to monitor the radiation level during the treatment and keep the family member at the safe distance. It can be used to monitor if anyone is under I-131 Treatment around you.

Product description

This AC Adapter has been specifically qualified by Mazur Instruments for use with the PRM-8000/9000 Geiger Counter and Nuclear Radiation Monitors. The included interchangeable plugs enable the AC adapter to be used virtually anywhere in the world providing the user with complete global flexibility. The Intelligent Power Control of the PRM-8000/9000 will sense that external power is present and will invoke the external power settings to enable such functionality as always-on display/backlight, while conserving internal battery capacity. When external power is removed, the PRM-8000/9000 will revert to the battery settings defined by the user.

• Qualified by Mazur Instruments for use with the PRM-8000/9000 Geiger counter and nuclear radiation monitors
• Input: 100 - 240V AC, output: 9V DC at 500 mA, cable length: 58-inches with L-type DC plug
• Wall-mount with interchangeable international AC plugs
• Energy efficiency Level V / RoHS, certifications: UL/CUL, TUV/CE, CB, SAA/Ctick
• One-year limited replacement warranty

User questions & answers

Question:	What is the polarity of the DC connector
Answer:	If I understand you question, the polarity of the DC plug that is inserted into the unit is negative on the ring, positive on the tip. So, negative outside and positive inside.

Product description

Carried everywhere your keys go, NukAlert's 24/7 constant radiation monitoring, alerts you if you are being exposed to dangerous levels of radiation. the NukAlert is a compact key chain attachable radiation Monitor & alarm. Monitoring is always on, using a built in long-life (ten+ year) battery. The devices range encompasses higher emergency radiation levels. There are 10 easily recognizable 'chirping' alarms. The NukAlert has a Patent-Pending 'State of the Art' Detector Technology that has been verified by independent National Radiological Laboratory. Each NukAlert is individually tested for radiation detection accuracy. Package includes an instruction manual with personal nuclear survival strategies. It Meets the FCC and European Community requirements for Electromagnetic Compatibility, emissions and susceptibility. it has also, passed EMP immunity tests and meets the MIL-STD-461D, RS105 standard. its has a 2 year warranty plus a 10 year prorated warranty. NukAlert is made in U.S.A. SPECIFICATIONS: * Detects Gamma & X-ray radiation: 20 keV to 2+ MeV * Detection Range: 100 mR/hr to 5,000 R/hr * Sensitivity: 100 mR/hr to 50 R/hr indicated in 10 ranges * Proportional Increasing Chirp Rate: 50 R/hr to 5,000 R/hr * Indication: Repeating groups of rapid countable chirps * Operational indicator: faint "ticking" = operating OK. * Alarm loudness: ~ 61 dBA (speaking volume) * Durability: Functional after 6' drop or submersion to 6' * Battery: Operational Life Expectancy @ room temp: - Non-alarming (normal operation) - 10 to 15 years - Alarming continuously at single chirp level - 3 years - Alarming continuously at highest alarm level - 3 months - See NEW Battery Replacement Program * Detector: Patented CdS photo resistor coupled to a rare earth phosphor scintillator # Accuracy: Within +/- 1 chirp # Response Time: Dose rate dependent: * ~3 - 4 min. @100mr/hr * seconds @ R/hr ranges

• Always "ON" 24/7, Includes long-life 10+ year battery
• Detection Range: 100 mR/hr to 5,000 R/hr, Gamma and X-rays from 20 keV to above 2 MeV
• 2 year regular warranty, 10 year prorated warranty
• Meets DoD EMP immunity standards
• Made in the U.S.A.

User questions & answers

Question:	Can this unit be taken thru TSA security Without setting off alarms
Answer:	It did not set alarms off for me. I put it in with my keys in the tray. There were no issues.
Question:	Where can I get the batteries replaced
Answer:	The company will if you send it to them. They are suppose to lasr 10 years, of course if no nuclear incidents.The company states that if you put the device next to your ear and you don't hear the internal clicks (at about 30-60 seconds) which is normal. If you hear nothing that means the battery is malfunctioning or dead. The company states to send the device back and they will replace it within the warranty.
Question:	Does this detect high nuclear activity in time to seek shelter or medical assistance? I'm wondering if this would be a good bug out alarm
Answer:	Yes. IT also detects imbeciles. Notice the constant alarming when you wear it.
Question:	Is it supposed to be ticking? It ticks twice every couple of seconds. Has been doing this nonstop for months
Answer:	To add to the other responders to your question, the quiet ticking has nothing to do with actual detection of radiation. Should your Nukalert pick up a significant amount of penetrating gamma radiation, it will respond with louder audible chirps about the volume of a human voice talking. This detector is designed for 'wartime' use to scout out medium to fairly high (and immediately dangerous) levels of nuclear radiation, not detect any low level background radiation. I hope that helps!

Product description

The compellingly priced PRM-7000 provides essential nuclear radiation awareness during a nuclear accident, event or emergency. The instrument is built upon the same long battery life, made in the US, platform as the PRM-8000 and PRM-9000, which have been the choice of governments, organizations and individuals around the world. The instrument is designed to similar specifications as devices used to address the radiation hazards faced by firefighters, HAZMAT teams, paramedics and other first responders. The PRM-7000 can be calibrated to the official international standards of accuracy required for regulatory work. Note, this product is not the best choice for testing food please consider the PRM-9000. Mazur Instruments uses only genuine detector tubes in all of its products, made in the US, by LND and does not rely on imported, cloned or "knock-off" detector tubes present in some lower priced products. The PRM-7000 is designed to be always-on collecting measurements and statistics enabling rapid environment assessment. Using only one key, users can scroll through several screens that display present, average, maximum and minimum measurements in uR/hr, mR/hr, uSv/hr, Counts per Second (CPS) or Counts per Minute (CPM), as well as time/date of maximum. The supplied standard alkaline 9-volt battery provides. The PRM-7000 can autonomously store up to 91,466 minutes or hours of time-stamped measurements. These measurements can then be uploaded to a PC in CSV format for analysis. A user-settable dose rate alarm sounds an audible alert when the measured radiation level exceeds that of the alarm level setting. The PRM-7000 includes abundant I/O options including support for headphones, external speakers, external power and PC/Mac USB data exchange (requires optional 3.5mm to USB adapter cable). Minimum energy sensitivity (35 keV). Gamma sensitivity: 450 CPM/mR/hr (Cs-137).

User questions & answers

Question:	Will this detect radiation in Alaskan Fish
Answer:	Dear Cindy! It does not detect Alpha, only Beta, X-Ray & Gamma! The radiation in your fish sample would have to be enough to exceed background radiation! If radiation is present it will detect it!
Question:	can i use this device to check the x-rays radiations levels out side x-ray rooms in side the hospital
Answer:	I BELIEVE THAT WOULD BE O.K.! JUST REMEMBER THE PRM-7000 DOES NOT MEASURE ALPHA EMISSIONS!!! THE PRODUCT DESCRIPTION ON AMAZON STATES THAT THE DEVICE MEASURES BETA, X-RAY, AND GAMMA RADIATION! HOPE THIS HELPS YOU! RANDY
Question:	For this detector, what is the conversion factor between mr/hr and cpm
Answer:	Hi! googled it and the conversion chart is listed under millirem conversion chart! However it is not maybe possible to have an exact conversion! When I used my first detector it was measured in rads! Then rem short for Roentgen! the rem is a measurement of radiation absorbed in tissue while the CPM is radiation emission! You would need to superimpose two three dimensional functions with the xyz epicenter and use Delta t1 for time evolved for millirems (tissue absorption is different from radioactive decay) and Delta t2 for time evolved for CPM. I just use Cpm or Cps-much easier! (unless you are using it in the medical field!Hope this helps and my conception of the process is correct!Best Regards,Randy
Question:	I'm prototyping the 7000 unit for first responders... what are the advantage(s) of the 9000? The descriptions were not conclusive
Answer:	The 9000 description reads to have reading capability of alpha, beta, gamma and xrays. Whereas the 7000 only has gamma reading ability. Purchasing the 7000 was a financial decision on my part. At half the cost of the 9000, the 7000 will read gamma radiation notifying me of danger. In the case of lab or food services inspection the 9000 would be a wiser choice. If I were a 1st Responder on site, I would appreciate a device able to sense all possible radioactive sources. My accounting dept would appreciate the device at a price range reasonable to outfit many 1st Responders. Understand that the 7000 was my choice because gamma radiation present would give me the warning I needed to back away and attempt another path. Hope this helps....

• Multiple high sensitivity sensors installed for detecting Power line, Smart meter, Cell phone, Microwave etc.
• Identify/recognize the common possible sources, such as Power line, Cell Tower, Microwave, Static etc.
• Safety suggestion lets you understand current situation instantly.
• Detects 5G network signal and RF up to 10Ghz
• Built-in RF Spectrum analyzer and GQ RF Browser for real time RF monitoring.

User questions & answers

Question:	All i want to know if this detector gq emp-390 will detect 5ghz wifi signal and 5g cell phone
Answer:	Yes it will detect 5GHz signal but not in all modes of operation. If it is the predominant source then the general Radio Frequency RF mode reading will reflect it. If it is a source mixed with others than all sources will be reported together as one value (sum/average over time...unknown. most likely average). It will not detect it in spectrum analyzer, by frequency, and show it's individual power level. Spectrum analyzer will detect 2.4GHz wifi. 5GHz is out of range of spectrum analyzer as is everything greater than 2.5GHz. It might detect presence of 5GHz data packet bytes in digital mode but I don't know for sure, have not tested this.
Question:	Can it tell you how much emf your cell phone emits
Answer:	yes it does, in 3 scales. some readings read a voltage per meter and another is electro-magnetic reading, I searched through alot and after receiving this I found it to be the best affordable technology in its class, and it even automatically identifies the difference between cell phone and power line EMF in digital readable format.
Question:	Will this device analyze a 5 gig wifi signal like it does a 2.4 or
Answer:	Yes, it does analyze 5 Ghz frequencies. If you are asking whether it will analyze 5G as in 5th generation Millimeter Waves, the answer is NO.. 5th Generation 5G will use frequencies between 30Ghz and 300Ghz... You can get one that costs about $40,000... As in, they are not available to the public .
Question:	Is the 5g wifi signal the same as the new 5g cell phone signal? will it measure the new 5g phones? it is confusing: it says: "rf up to 10 ghz
Answer:	The 5G wifi is referring to 5Ghz Wifi, and it is covered by this meter RF band. The 5G cell phone network is referring to 5th Generation cell phone network, it is nothing to do with 5GHz, basically its base band is much higher than 5Ghz

Product features

New display maximizes the amount of information

• All-in-One display lets you see reading from all sensors at once.
• Advanced features and multi-sensors to ensure best detection from EMF, EF and RF.
• Compact design for easy testing and measurement.
• Safety suggestion lets you understand current situation instantly.
• Radiation source recognition provide fastest way to find out the radiation source.

Classic display option is quick to adapt application

• With traditional analog style display, the data becomes even easier and faster to understand.
• Left and right vertical bars are also indications of the EF and EMF radiation level in glance.
• Safety suggestion in large font for easier reading.
• Real Time clock displays current time for time sensitive testing.
• Front LED visualizes alarm when triggered.

Real-Time EMF EF Graph

• Presents exact changes of EMF and EF radiation level been detected in past 45 seconds.
• The right side of graph shows a reading for both EMF and EF.

RF Spectrum Analyzer

• Advanced users are able to use built-in RF Spectrum Analyzer to discover the RF signal power in a specific frequency.
• This graph shows two RF signal that has been detected at same time: Microwave oven and WiFi signal.

RF Browser

• GQ RF Browser is a unique feature of GQ EMF detector. The real-time graph is based on high sensitivity sensors.
• This graph shows a close by cell phone that just received a text message.

Real-Time Power Distribution Histogram

• RF power distribution is another important factor to let us understand how the RF radiation power distributed during the period.
• This graph shows the highest RF power is 6.47% of total at 0.049 milliWatts per square meter during the testing period.

Product description

The GCA-07W is a handheld personal nuclear radiation detector. A proven track record for detecting nuclear radiation in school physics lab, industrial settings, transport containers, top soil, granite table tops, scrap metal, oil fields, objects and interior spaces.



The external wand makes it easier to search materials and surfaces for radioactivity. The GCA-07W detects Alpha, Beta, X-ray and Gamma radiation above 3 MeV, 50 KeV, and 7 KeV respectively.



Easy to read LCD is a 2 line by 16 characters that provides a current count and radiation level readout. Simple front panel instrument controls make the GCA-07W easy to use. Toggle switches control all the front panel options. User can select a time period, type of measurements (Imperial or Metric). Measurements (counts per second) are converted into radiation levels (mR/hr or mSv/hr). Time selection switch allows Counts Per Second (CPS) or Counts Per Minute (CPM) mode.



Factory calibrated using a NIST traceable source to ensure accurate measurements. Our NRC certification is available at additional cost from the manufacturer. The NRC certification certifies your Geiger counter has passed ANSI-STD N323A calibration using a NIST traceable source from an independent US licensed laboratory conforming to United States Nuclear Regulatory Commission NRC regulations 10-CFR-34 and 10-CFR-35 standards (available at additional costs through the manufacturer).



Options: Jack for Headphones or External Speaker. External Power Supply included. 3.5mm Data Port for WIN PC and microcontroller interface. The WIN PC program requires optional 3.5mm to USB data cable.





Secondary indicators; audio (clicks) and visual (LED) included. 9V battery (mobile operation) not included.

User questions & answers

Question:	Does this unit beep or click? I have seen mixed info. Could someone upload a video of it
Answer:	That's an interesting question. The audio output is a tone generator. But that audio output is pulsed quickly so the tone sounds more like a click than a beep. Technically, they're both right.
Question:	Does it have an end sensitive wand
Answer:	I'm not sure what you mean here. The wand has an open end that exposes the mica window of the GM tube for the detection of alpha particles. In the photograph the wand has a plastic end cap on it that I recommend you keep on unless you are specifically trying to detect alpha particles. The mica window of the GM tube is thin and easily damaged.
Question:	Will this measure radon in your house
Answer:	The GCA-07W is sensitive to alpha radiation given off by radon. However this is not the instrument to use to detect or measure Radon in the home. There are specialty instruments and equipment available for just this purpose.
Question:	Can this measure radiation in ocean fish
Answer:	This is a complex question. The GCA-07W can detect alpha, beta, x-ray and gamma radiation. Checking fish or food for radioactive contamination is a little difficult and Geiger counters, (from us or any other manufacturer) is not the ideal instrument to do so, here's why. The GCA-07W Geiger counter can detect alpha radiation. However if the fish (or food) being tested has a alpha radiation emitter internally, the food itself will block the alpha radiation and stop it from being detected. If the alpha radiation contamination is on the surface of the fish (unlikely), it can be detected. Similarly, if the fish has a beta radiation contamination internally, let's say a SR-90 contamination, the water in the flesh of the fish will effectively block the beta radiation from being detected. Again if the beta contamination is on the surface of the fish (unlikely), it can be detected. With gamma radiation the situation changes. Gamma radiation can penetrate the flesh of the fish to be detected. The problem arises is that low level contamination gamma radiation from let's say a CS-137 contamination will be indistinguishable from normal background radiation. So to test for this contamination , one method a laboratory may perform is a gamma spectroscopy (scintillation detector) to determine the source of the radiation. In the case of testing for alpha and beta radiation mentioned before, a lab might incinerate the food or fish in question down to ash. Without the water blocking radiation it becomes easier to test the material for beta and alpha contamination.On the Images website we have a number of nuclear experiments and articles. We have an article on testing food for radioactive contamination that goes into greater detail than I can here.I hope this information helps.