Forums Reviews & Commentary >> Review Discussions >> IdealRatio Rodnik 3 Portable Radiation Detector

Message started by Administrator on Jun 20th, 2019, 7:06pm

Title: IdealRatio Rodnik 3 Portable Radiation Detector
Post by Administrator on Jun 20th, 2019, 7:06pm

This thread is for the discussion of the review “IdealRatio” “Rodnik 3” Portable Radiation Detector.

Of course, you may want to read the review first:

The Unboxing Video is here: (

Title: Re: IdealRatio Rodnik 3 Portable Radiation Detecto
Post by Administrator on Jun 20th, 2019, 9:05pm

Administrative Note: A post prior to this one, detailing how I found a number of radioactive things while on vacation, was lost.  In that post, I had mentioned that I visited the Smithsonian National Museum of Natural History in Washington, DC, USA.  In that museum, there is a display of Radioactive Minerals.  While standing in front of the display, I realized that my Rodnik 3 Radation Detector was in alarm mode in my pocket.

Is the display of Radioactive Minerals at the Smithsonian National Museum of Natural History dangerous to the public?

In the post above, I mention that the display of Radioactive Minerals at the Smithsonian National Museum of Natural History in Washington, DC. immediately made my Rodnik 3 radiation "Dosimeter" alarm in my pocket just from walking in front of the glass.

In the photo below, It is reading 7.53µSv/h.  Holding it there a bit longer may have had it reach 10µSv/h.
The Rodnik 3 responding the a display of Radioactive minerals at the Smithsonian National Museum of Natural History, Washington, DC, USA. Photo copyright 2019

Is this dangerous to the public walking by it, or casually reading about the displayed minerals?

Well, first of all, to be clear this is really measuring ionizing radiation penetrating the glass.  Yeah -- ionizing radiation.  Not the stuff from your mobile phone or microwave oven.  That's RF radiation, and the Rodnik 3 does not measure that.  We are talking about ionizing radiation -- The real Chernobyl or Fukushima stuff.

More than that, normal background radiation is generally about 0.10µSv/h (rounded for easy math), so it is at least 100 times the normal background radiation where most people live.

That sounds dangerous... but is it really dangerous for someone browsing this particular display?

Well, let's put it in perspective.  Using the radiation dosage chart (Ref: We can compare it to some other things people commonly do.

Note the first, single green dot in the second section -- Chest X-ray -- 20µSv.  So studying the display for two full hours would be equivalent to a single chest X-ray.  However, I don't think people typically spend two hours studying that display.  In most cases people only spent a minute or two perusing any of the displays.

Using the same chart, we can look at it another way.  Look at Mammogram -- 400µSv.  If you stood in front of the display for an entire work week (5 days x 8 hours a day), and then left to get a mammogram, you would get an equal dose from the mammogram, as from the display at the Smithsonian.

So... Enjoy the display of Radioactive minerals at the Smithsonian National Museum of Natural History.  Read it, study it leisurely. Unless you spend all day, every day, with your -- um -- "mammogram parts" -- pressed up against the glass, it's really pretty safe.

I should also mention that the Rodnik 3 detected radiation from a few other individual mineral samples in other displays that contained heavier elements, as one would expect.  None of these produced nearly as high a reading on the Rodnik 3 as the Radioactive minerals display.

Title: Re: IdealRatio Rodnik 3 Portable Radiation Detecto
Post by Administrator on Jun 24th, 2019, 8:25pm

Another note on displays pertaining to Radiation at the Smithsonian National Museum of Natural History.

In another room, there is a different display on radiation.  This display contains an analog radiation meter (Geiger counter) and a chunk of radioactive ore attached to a rotating disk.  The intent is to show that the Geiger counter registers as the ore passes near the Geiger probe.

This is not the display I am referring to in the above posts.  While the radiation in front of the display with the rotating ore was detectable as I stood in front of this display, it was no where near the levels near the display of radioactive minerals in the minerals and gems area.

Title: Re: IdealRatio Rodnik 3 Portable Radiation Detecto
Post by Administrator on Aug 13th, 2019, 8:27pm

... But does it work on a Plane?

Sorry if you were expecting some sort of clever rhyme there.

As readers interested in ionizing radiation and devices for measuring radiation probably already know, our atmosphere shields us from lots of space radiation (cosmic rays).  A commercial airline flight, flying at about 40,000 feet  (12,000 meters) is above the majority of this shielding atmosphere.  Yes, planes are generally made of metal, but a very thin aluminium skin is not going to make up for 10's of thousands of feet of atmosphere.  As a result, all passengers on commercial flights are subject to a significant dose of radiation every time they fly.  And, Yes, it's worse for frequent flyers, those on long-haul (international) flights, and of course, pilots and flight attendants.

So can the Rodnik 3 show us the dose a passenger receives? Is it legal to take on a plane?

I recently went on a business trip, and I took my Rodnik 3 with me.  I tossed it in my backpack with other typical electronic gadgets, such as 2 laptops, associated cables, mice, chargers, etc.  It passed through security with no attention from those very friendly folks with the latex gloves.  Carrying radioactive materials on a commercial flight is illegal, but the Rodnik 3, and similar devices detect radiation.  They are not, themselves, radioactive, and taking one on a plane is no different than taking other consumer electronics.

Here's a screen shot from after the plane reached the top of climb:
Rodnik 3 Ionizing Radiation Meter showing typical radiation levels on a commercial airline flight at 39,000 feet.  Image adjusted for display contrast only.

A few observations:
  • The contrast of the display was edited due to the strong sunlight only.  As I have mentioned before, the display of the Rodnik 3 is actually very crisp and easy to read.
  • This was an east-bound flight, so we must have been at an odd multiple of thousands of feet -- I'm assuming 39,000 feet in this case.
  • While the shot did not catch the LED on, it is flashing as indicated by the 'A' for alarm.
  • There is actually an advantage to the audible alarm being so quiet.  With the noise of the aircraft, other passengers won't notice the alarm. Note that I am covering the holes over the buzzer just to be sure.

The display is indicating 3.41 µSv/h.  Again, using my round number of 0.10  µSv/h for normal sea-level background levels, I am receiving 34.1 times the normal radiation level.

This coincides very closely to what is listed on for an "average" flight (scroll to "Cosmic Rays in the Atmosphere"):

Descending back into the thick air of a Florida summer, the counts went down quickly.  By the time the fight attendants announced we were descending through 10,000 feet, the Rodnik 3 only indicated about 2 -3 times normal background, although by looking at the developing cumulus clouds at that same time, I estimate we were more likely between 8,000 and 5,000 feet when that announcement was made.

This exercise also points out one of the biggest deficiencies of the Rodnik 3.  As mentioned in the review, it does not measure accumulated dose. A meter like the Ecotest MKS-05 "Terra-P" (Reviewed Here: has an accumulated dose feature that could be reset before a flight, and measure the total accumulated dose for a specific flight. In this mode, it could even continue to record accumulated dose while placed in checked luggage.


Title: Re: IdealRatio Rodnik 3 Portable Radiation Detecto
Post by Administrator on Dec 30th, 2020, 11:04am

Here's another "Have I Found Anything Radioactive?"

I did:

In this picture, my IdealRatio Rodnik 3 is showing approximately 50x background a few centimeters from a rather unremarkable looking rock.

Based on a (very) little research I did while writing this post, I believe this may be a specimen of coffinite.

Before you ask why I would own something that is highly radioactive, and with a name that has a close association with death, I should mention that coffinite is named after American geologist Reuben Clare Coffin.  The name of the mineral is just a coincidence of a rather unfortunate last name.  While coffinite does contain uranium, the name was not meant to portray this mineral as any more or less dangerous than any other naturally occurring mineral that contains radioactive elements.

The assumption that the stone in the picture is coffinite is based on pictures from a Google Images search that seem to show similar grayish rocks with traces of yellow crystals.  In addition, coffinite is the 2nd most prevalent uranium-containing mineral, so simple statistics show good odds that it is in fact coffinite.

So how did I come to posses this bit of hyperactive nature?

I would have never found this stone without my IdealRatio Rodnik 3.  I was at my local flea market.  There are 2 vendors there that specifically sell crystals, stones and minerals, but this rock didn't come from them.  I did buy a piece of tumbled green apatite from the larger vendor.  I learned that green apatite seems to generally be more radioactive than blue apatite.

I also purchased a tumbled malachite stone - not for it's radioactivity (it isn't radioactive), but for the name association with another project covered here on (http://"").

Having passed the crystal/stone vendors, and in fact reached the very end of the market, I came across a man with several full tables of random rocks, as well as quite a lot of abalone shells.

I don't remember if it was something the seller said, a sign or label, or just the general look of the various rocks, but I got the impression that the rocks were from the Western United States.

I waved my Rodnik 3 over the boxes, and it gave a flew clicks over a specific corner of one box.  Of course random events of cosmic or local nature can cause a momentary jump in counts, so I waived the counter over the same area again, and again it reacted. I picked up some rocks in that part of the box, but when  I tested those rocks while holding them away from the box, my Rodnik 3 began to decrease back toward a normal background reading.  With some of the rocks moved away, I again held the Rodnik 3 over the box.  It began a steady stream of beeps followed almost immediately by the alarm mode.

Something in the box was "hot", and the other rocks had basically been shielding it.  So you basically know the full story.  The source of the radioactivity was the small stone pictured above.  I paid the man $3 and took my rock home with me (but not in my pocket.)

If I see the same vendor again, I will ask him if he knows any more about were the rocks came from. Forums » Powered by YaBB 2.1!
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