Is my used Geiger counter radioactive?

In summary: I saw on YouTube some people put the Geiger counter on a banana and it read like it was radioactive.In summary, a Geiger counter can measure background radiation levels around 0.1uSv/hr.
  • #1
justamom
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TL;DR Summary
Worried about radioactive contamination from a possibly used Geiger counter
I’m a mom and was worried about radiation in the new house we moved into, so I ordered a Geiger counter (the GQ gmc 500 plus) on amazon. But I noticed the screen protector film wasn’t pressed on all the way so there were some bubbles, there also was one scratch on the screen protector film and some scratches on the Geiger counter plastic itself, now I’m worried Amazon sent me a used product. Since amazon sometimes sells returned items as new. What if someone used it at Chernobyl or touched it to radioactive objects or materials and it’s contaminated? Now my hands my house my children are contaminated with radioactive materials? Also how do I know if it is radioactive or not? Also I bought it twice, the first one I bought had a stain on the manual and after placing the Geiger counter on the manual with the stains, it started reading a consistent 0.18-0.27uSv/hour. The second one I bought came scratched and it read around 0.12-0.15uSv/hour. Why did the first one I bought read higher after it touched the stained manual? Maybe the manual had radioactive contamination? Can a Geiger counter detect if itself is radioactive or has radioactive contamination?
 
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  • #2
Everything in the world is radioactive, even you and me. It is a question of where the Geiger counter has been before, whether itself is more radioactive than the environment. I think it is safe to say that it wasn't used in Cernobyl nor in Fukushima, so chance are low that it is overly radioactive. And, yes, it counts itself, too. If it is radioactive itself (and works correctly) then you will measure this, too.
 
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  • #3
fresh_42 said:
Everything in the world is radioactive, even you and me. It is a question of where the Geiger counter has been before, whether itself is more radioactive than the environment. I think it is safe to say that it wasn't used in Cernobyl nor in Fukushima, so chance are low that it is overly radioactive. And, yes, it counts itself, too. If it is radioactive itself (and works correctly) then you will measure this, too.

so did the Geiger counters contaminate my hands and my house and my children with radioactive materials?
 
  • #4
justamom said:
so did the Geiger counters contaminate my hands and my house and my children with radioactive materials?
No.

It is theoretically possible, if it e.g. has been used on 3-mile-island 1979, but this is more than unlikely. It is probably not any more radioactive than the next concrete wall is. To become radioactive, it had to be exposed to a radioactive environment over some time. There is no reason to assume this was the case.

You can simply test it: switch it on and read the scale.
 
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  • #5
A reading of around 0.1uSv/hr would be a typical background reading for areas not known for unusual radiation dose rates. So your reading should not raise any suspicions or concerns. To get the best baseline reading take the reading outside your house. and compare that reading to one taken inside your house. The difference between the two should be negligible.

The difference in the readings between the two detectors you received is not significant because the number is derived from a calibration factor which may not super accurate depending on who and what protocol was used to determine this factor. These instruments are not precision devices.

Also, these instruments are most effectively used if you know what type of radiation you are detecting and the radiation that the instrument was calibrated for. The calibration is for one particular type of radiation and is not that accurate for the whole range the instrument is sensitive to.

The biggest issue with radiation levels in houses is radon for which a GM counter is unsuitable. If you are concerned about radon then you can obtain kits from survey companies that will give you a very good estimate of the level and probably advice for any remediation if warranted.

As for whether the instrument was contaminated you can only determine that with another detector.
 
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  • #6
0.1-0.27 uSv/hour is 1-2.4 mSv/year. This is on the low end of average. I would not worry about this. In particular because the biggest variable risk is radon and this device is not going to be able to measure radon.
 
  • #7
fresh_42 said:
No.

It is theoretically possible, if it e.g. has been used on 3-mile-island 1979, but this is more than unlikely. It is probably not any more radioactive than the next concrete wall is. To become radioactive, it had to be exposed to a radioactive environment over some time. There is no reason to assume this was the case.

You can simply test it: switch it on and read the scale.

like what if someone bought it before and used it to test radioactive materials, I saw on YouTube some people put the Geiger counter directly on top of uranium ore or radium paint. Also some even took the Geiger counter to Chernobyl to test the dirt for radiation etc.

also the numbers the Geiger counters were reading, the first one read 0.18-0.27uSv/hour and the second was 0.12-0.15uSv/hour, are those considered normal background radiation or are those high/indicative of radioactive contamination?

I’m so worried my hands and my kids and my car and house is contaminated with radioactive dust or liquid etc...
 
  • #8
You must not be worried. Even if someone brought to Cernobyl and back it won't probably be contaminated, because a) you don't get very close to the actual plant, and b) you won't bring back any dirt. The smoke of a cigarette is likely more contaminated than your device! You say that you measured around ##0.15 \mu S##. For comparison: the allowed value at the fence of a German nuclear power plant is according to Greenpeace ##0.3 mS##. Hence your device measures the ##0.002##-th part of it. The x-rays at your dentist are likely more damaging than that.
 
  • #9
gleem said:
A reading of around 0.1uSv/hr would be a typical background reading for areas not known for unusual radiation dose rates. So your reading should not raise any suspicions or concerns. To get the best baseline reading take the reading outside your house. and compare that reading to one taken inside your house. The difference between the two should be negligible.

The difference in the readings between the two detectors you received is not significant because the number is derived from a calibration factor which may not super accurate depending on who and what protocol was used to determine this factor. These instruments are not precision devices.

Also, these instruments are most effectively used if you know what type of radiation you are detecting and the radiation that the instrument was calibrated for. The calibration is for one particular type of radiation and is not that accurate for the whole range the instrument is sensitive to.

The biggest issue with radiation levels in houses is radon for which a GM counter is unsuitable. If you are concerned about radon then you can obtain kits from survey companies that will give you a very good estimate of the level and probably advice for any remediation if warranted.

As for whether the instrument was contaminated you can only determine that with another detector.

so the Geiger counter is contaminated with radioactive materials?
 
  • #10
Vanadium 50 said:
0.1-0.27 uSv/hour is 1-2.4 mSv/year. This is on the low end of average. I would not worry about this. In particular because the biggest variable risk is radon and this device is not going to be able to measure radon.
But what if the Geiger counter was contaminated with radioactive materials then it got on my hands and all over my house, I also carried my baby after using the Geiger counter and didn’t wash my hands and my baby touched my hands and then rubbed his eyes/sucked his finger
 
  • #11
justamom said:
so the Geiger counter is contaminated with radioactive materials?
Not more than you are, too!
 
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  • #12
justamom said:
But what if the Geiger counter was contaminated with radioactive materials then it got on my hands and all over my house, I also carried my baby after using the Geiger counter and didn’t wash my hands and my baby touched my hands and then rubbed his eyes/sucked his finger
You cannot have zero radioactivity. It simply does not exist. If there were radioactive material which could find a way to your or your baby's body, then you would have measured higher values than you actually did. It is safe.
 
  • #13
fresh_42 said:
You cannot have zero radioactivity. It simply does not exist. If there were radioactive material which could find a way to your or your baby's body, then you would have measured higher values than you actually did. It is safe.
Thank you, so 100% sure I did not contaminate my hands and my baby and our house with radioactive materials from the used Geiger counter?
 
  • #14
justamom said:
Thank you, so 100% sure I did not contaminate my hands and my baby and our house with radioactive materials from the used Geiger counter?
Yes. Given that we still talk about micro Sievert.
 
  • #15
justamom said:
so the Geiger counter is contaminated with radioactive materials?

As I stated the normal background dose rates are about 0.1 uSv/hr. The readings you measured are consistent with normal background rates. I would not be concerned about any possible contamination of the instrument based on your readings.

Any radiation survey instrument should be supplied with a weak radioactive check source to test the meter before it is used. When placed at a designated spot near the instrument's sensor a specific reading should occur. The expected reading should be supplied with the instrument it to assure that it is working properly. Do you have one of these sources and the expected reading?

For the benefit of any reader of this thread let me state that if you have a concern about radiation contact a person trained in evaluating environmental radiation levels. Most large hospitals have persons who can do this or can direct you to one that can. Interpreting the readings of any radiation detector is not as trivial as reading a meter.
 
  • #16
gleem said:
Any radiation survey instrument should be supplied with a weak radioactive check source to test the meter before it is used.

This is a $100 device, and it doesn't even have a probe. I very much doubt it has a check source. It's not really a measurement tool. More of a toy.
 
  • #17
@justamom please reread the thread slowly and pay particular attention to the word "radon". You're fearing the wrong thing.
 
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  • #18
russ_watters said:
@justamom please reread the thread slowly and pay particular attention to the word "radon". You're fearing the wrong thing.
But why doesn't a Geiger counter detect radon? Natural radon decays over ##\alpha ## particles. Don't they measure ##\alpha ## decay?
 
  • #19
fresh_42 said:
Don't they measure decay?

No. Alphas don't penetrate the window.
 
  • #20
fresh_42 said:
But why doesn't a Geiger counter detect radon? Natural radon decays over α particles. Don't they measure α decay?

The usual GM counter tube is too thick to detect alpha. It can detect the gammas but the low permissible concentration (4 pCi/liter or 0.15 Bq/liter) of Rn coupled with the low detection efficiency of the GM tube make it impossible to evaluate a hazard with this type of instrument. The best way to evaluate Rn concentration is to use an air sampler that forces the air through a charcoal filter at a given rate for an extended time and then measure the gammas from the filter with a high-efficiency scintillation well counter or similar device. You need to measure for an extended time because the Rn concentration can vary significantly during the day and with atmospheric pressure.
 
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  • #21
Go to your local grocery store and purchase a large canister of no-sodium salt substitute. Measure it with your counter. Now consider that you just measured food.

BoB
 
  • #22
rbelli1 said:
no-sodium salt substitute
Or:
 
  • #23
Vanadium 50 said:
No. Alphas don't penetrate the window.
How useless then. I mean, when am I exposed to ionization beams except at the dentist, or in a hospital? Who wants to know their exposure during flights or on winter vacation?
 
  • #24
fresh_42 said:
How useless then. I mean, when am I exposed to ionization beams except at the dentist, or in a hospital? Who wants to know their exposure during flights or on winter vacation?
Well, if it's a ski vacation, make sure to wear sunscreen -- it won't measure that ionizing radiation either.

That wasn't my point anyway though; my point was the OP didn't seem to notice the word "radon" and was fixated on the Geiger counter being contaminated. Fearing the Geiger counter, not the [potential for] deadly gas in the basement.

There's such a thing as rational fear or concern. It's the kind that you develop through thought, logic and learning, not by daydreaming and wildly speculating about what can kill you. Because pretty much everything can kill you if you use it wrong enough. So you have to put real thought into what to be concerned about/fear.
 
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  • #25
fresh_42 said:
How useless then

The issue with radon is not the effect upon the radiation background. It is all short-period radon progenies which are responsible for most of radon's biological effects. They are often charged and adhere to dust particles and lung tissue. You will not be able to measure this with a simple meter.
Sorry but life is complicated.
 
  • #26
fresh_42 said:
How useless then.

Well, it's pretty much a toy. If you want to measure radon, you don't get this. You get a radon test kit.
 
  • #27
russ_watters said:
Well, if it's a ski vacation, make sure to wear sunscreen -- it won't measure that ionizing radiation either.

That wasn't my point anyway though; my point was the OP didn't seem to notice the word "radon" and was fixated on the Geiger counter being contaminated. Fearing the Geiger counter, not the [potential for] deadly gas in the basement.

There's such a thing as rational fear or concern. It's the kind that you develop through thought, logic and learning, not by daydreaming and wildly speculating about what can kill you. Because pretty much everything can kill you if you use it wrong enough. So you have to put real thought into what to be concerned about/fear.

We don’t have a basement, I guess radon is out of my control because it’s something that’s in the ground/air. But I feel so much guilt for buying the Geiger counter on amazon when Amazon sells used/returned items as new sometimes and worried I further exposed my baby and kids to ionizing radiation from the contaminated Geiger counter, and that the radioactive materials could be on my hands, on and in my children, all over our house, in our car etc...
 
  • #28
russ_watters said:
That wasn't my point anyway though; my point was the OP didn't seem to notice the word "radon" and was fixated on the Geiger counter being contaminated. Fearing the Geiger counter, not the [potential for] deadly gas in the basement.
I know, that's why I liked that you pointed out the radon problem again. But I'm a smoker, so I am automatically exposed to radon more than usual.
 
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  • #29
russ_watters said:
Well, if it's a ski vacation, make sure to wear sunscreen -- it won't measure that ionizing radiation either.

That wasn't my point anyway though; my point was the OP didn't seem to notice the word "radon" and was fixated on the Geiger counter being contaminated. Fearing the Geiger counter, not the [potential for] deadly gas in the basement.

There's such a thing as rational fear or concern. It's the kind that you develop through thought, logic and learning, not by daydreaming and wildly speculating about what can kill you. Because pretty much everything can kill you if you use it wrong enough. So you have to put real thought into what to be concerned about/fear.
Also can u please confirm if my fears/worries about a contaminated Geiger counter contaminating me and my kids and house with radioactive materials is irrational or not? I have contamination OCD around things like mercury, lead, asbestos, toxic chemicals, but now it seemed to fixate on radiation/radioactive materials... it got worse after having children as I worry for them and their health...
 
  • #30
It is very unlikely that your Geiger counter purchase spread any contamination. Also if it was leaving (i e spreading) contamination it would have measured it. Your reading were fine! That being said worry about the big dangers for your kids:
Car seats and belts
second hand smoke
Firearms in the home
Good food
Near Earth asteroids
The electric grid
Fascists of all kinds
Seriously you need to prioritize as rationally as you can. Then do what you can. We all have our irrational fears
 
  • #31
If you truly value the health and lives of your children, think about the fact that the average life span in 47 countries is longer than in the U.S. The main difference between the U.S. and those countries is that those people have healthier diets and they get more exercise. This chart is from Pocket World in Figures, 2018 Edition, by The Economist magazine.
Life Expectancy.jpg
 
  • #32
fresh_42 said:
For comparison: the allowed value at the fence of a German nuclear power plant is according to Greenpeace ##0.3 mS##. Hence your device measures the ##0.002##-th part of it. The x-rays at your dentist are likely more damaging than that.
0.3 mSv per year (over the natural background radiation). A year has 10,000 hours, so that's 0.03 uSv/hour extra.
Anyone receiving 0.3 mSv per hour would be an emergency that makes international news.
 
  • #33
mfb said:
0.3 mSv per year (over the natural background radiation). A year has 10,000 hours, so that's 0.03 uSv/hour extra.
Anyone receiving 0.3 mSv per hour would be an emergency that makes international news.
Isn’t 0.03uSv/hour even less than what was recording at my house, which was 0.27uSv per hour at the highest??
 
  • #34
over the natural background radiation
Nuclear power plants are not allowed to increase the radiation level by more than that. The natural radiation level can be whatever it wants (and it's over 1 uSv/hour in some places).
And that's the upper limit. In practice the increase is far smaller.
 
  • #35
hutchphd said:
It is very unlikely that your Geiger counter purchase spread any contamination. Also if it was leaving (i e spreading) contamination it would have measured it. Your reading were fine! That being said worry about the big dangers for your kids:
Car seats and belts
second hand smoke
Firearms in the home
Good food
Near Earth asteroids
The electric grid
Fascists of all kinds
Seriously you need to prioritize as rationally as you can. Then do what you can. We all have our irrational fears

What would the reading be if the Geiger counter was contaminated with radioactive materials?
 
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