The Limitations of Measuring and Reporting Dose Rate from Radioactive Objects

Why is using a dose rate to measure an object not always a meaningful way to convey information?  If not, what is?

When it comes to assessing the potential hazards of materials, measuring and reporting the dose rate emitted by a rock or any other radioactive object might seem like a straightforward approach. However, relying solely on this method can lead to misunderstandings and misinterpretations of the actual risks involved. In this article, we’ll explore why measuring dose rate alone isn’t a reliable way to convey meaningful information about radioactive objects.

The Complexity of Radioactivity Measurement

Radiation measurement is a multifaceted process that involves various technologies and detection components. Different types of handheld radiation measuring equipment utilize different methods to detect radiation, such as Geiger-Mueller (GM) tubes, scintillation detectors, and semiconductor detectors. Each type has its own strengths and limitations, making it crucial to understand the nuances of radiation detection before drawing conclusions from measurement data.

Limitations of Dose Rate Measurement

Measuring dose rate alone may not provide an accurate representation of the actual radiation hazard posed by a radioactive object. Here’s why:

Variability in Radiation Types: Different radioactive isotopes emit different types of radiation, such as alpha, beta, and gamma radiation, each with varying penetration depths and biological effects. Handheld radiation detectors may not differentiate between these types, leading to an oversimplified assessment of radiation risk.

Energy Dependence: Some radiation detectors are more sensitive to certain energy ranges than others. For instance, GM tubes are commonly used for detecting low to medium-energy gamma radiation but may not be as effective for detecting high-energy gamma radiation or beta particles. This energy dependence can affect the accuracy of dose rate measurements.

Shielding Effects: The presence of shielding materials, such as lead or concrete, can significantly attenuate radiation and affect dose rate measurements. Without accounting for shielding effects, reported dose rates may not accurately reflect the actual radiation exposure in a given environment.

Discrepancies in Measurement Readings

Due to differences in design, technology, and calibration standards, two calibrated radiation detectors may yield widely varying measurements when exposed to the same radioactive source. For example, a Geiger-Mueller counter and a scintillation detector may register varying dose rates for identical radiation fields due to their inherent detection mechanisms and response characteristics.

Dose Rate vs. Activity Concentration

One of the key distinctions to grasp is the difference between dose rate and activity concentration. Dose rate refers to the amount of radiation absorbed per unit of time, typically measured in sieverts per hour (Sv/hr) or millisieverts per hour (mSv/hr). Activity concentration, on the other hand, quantifies the amount of radioactive material present in a given volume or mass of a substance, usually expressed in becquerels per kilogram (Bq/kg) or becquerels per liter (Bq/L).


Activity refers to the rate at which a radioactive sample undergoes radioactive decay. It is a measure of the number of radioactive decays occurring per unit of time and is typically expressed in units such as becquerels (Bq) or curies (Ci). For example, if a sample has an activity of 1000 Bq, it means that 1000 radioactive decays occur within that sample per second.

Activity Vs. Count Rate

Activity describes the intrinsic radioactivity of a sample based on its rate of radioactive decay, while count rate measures the rate at which a radiation detector detects radiation events. While related, they serve different purposes in assessing radioactivity.


Precision in the context of measurement refers to the degree of repeatability or consistency in obtaining the same result when a quantity is measured multiple times under identical conditions. Essentially, it assesses how close multiple measurements are to each other. A measurement is considered precise if it yields very similar results upon repeated trials, indicating low variability or scatter in the data points. Precision does not necessarily imply accuracy; it focuses solely on the consistency of measurements relative to each other.


The variability in dose measurement readings between different types of calibrated devices highlights the necessity to use a more meaningful way of conveying information. Precision can be used as a meaningful way to convey information because a count rate measurement any specific device can be expected to be repeatable across all properly functioning properly calibrated devices of the same model.

What is the Definition of SDR?

What is SDR? Here we explore its definition and significance. SDR stands for Software Defined Radio. Today, the versatile processing capability of computers and mobile devices can be used to replace much of the electronic hardware components of traditional radio receivers and, to a degree, transmitters. A rather basic radio receiving module that manages to feed relatively raw baseband data into a device capable of running software allows software to take over processing from that point on, instead of relying on traditional radio circuitry to focus on bandwidth and tune, filter signals, and demodulate them using any given mode such as AM or FM, or protocol such as Slow Scan Television (SSTV) to turn them into usable signals and even show you where outstanding signals lie on the band, as discreet spikes on a spectrum analyzer graph.

Definition of SDR visual aid

The author’s 12 MHz-ish signals available at the time of writing, via Airspy’s SDR# freeware, using an upconverter-equipped RTL-SDR dongle on a PC, and a homemade, outdoor  antenna.

A revolution happened when European-based MPEG video broadcasting known as “digital terrestrial television” (as opposed to satellite), specifically named Digital Video Broadcasting – Terrestrial (DVB-T) spawned the mass production of a USB dongle featuring the 8-bit processing chipset, the famed RTL2832U. This was the release of the DVB-T USB TV tuner dongle originally meant for a rather finite purpose of watching television on a computer in 1998.

Steve Markgraf and the company Osmocom, along with Eric Fry and Antti Palosaari, discovered the inexpensive device could be “hacked” and used with custom-made drivers allowing an enormous swath of the radio spectrum, from kilohertz to gigahertz, to be accessed and interpreted with any software they wished. As RTL-SDR.com puts it, the discovery, “…became extremely popular and has democratized access to the radio spectrum”. The RTL-SDR was born. Anyone with around $20 (now less) and a computer with an adequate sound card or equivalent could now download free, open-source software such as SDRsharp (SDR#).

Inside a DVB-T USB dongle using Realtek RTL2832U (IC on right) as controller and Rafael Micro R820T (IC on left) as tuner

Now many, more sophisticated SDR’s exist, but RTL-based dongles are still a major player on the scene due to affordability and surprising capability. One of the most useful mods to the traditional hardware is an “upconverter” chipset addition that uses actual electronics to convert lower frequencies (such as traditional, broadcast AM radio and shortwave) into the VHF or UHF frequencies the RTL-SDR is properly equipped to handle. These lower bands may be accessed using a plain RTL-SDR that does not possess an upconverter, using only software means (and sometimes a jumper mod) but, if the hobbyists is particularly interested in frequencies below VHF, the extra $30 or $40 (for a total of $50 or $60) is worth the added expense in terms of efficiency and performance.

For $60 the author of this article was looking at countless spikes representing individual radio signals on a spectrum analysis graph, bouncing in between modes, and “surveilling” the world in manner virtually befitting the CIA just a few years prior. Users occasionally hear genuine, eerie spy “numbers stations”, receive images from astronaut or cosmonaut radio hobbyists on the International Space Station, and it has caused a bit of a revival in shortwave radio listening. With practice you can even intercept NOAA satellite signals and rectify them into satellite imagery of your part of the globe. VHF projects like this may be achieved with a simple antenna set of traditional TV “rabbit ears”, albeit better they are stationed outside. Even radio astronomy is on the SDR hobbyists menu.

SDR has opened up a world of adventure and exploration of a remarkable amount of the EM spectrum for pennies on the dollar – a true revolution for the radio enthusiast.

Safety & Radioactive Ore for Sale

Here we examine some issues surrounding the safety of radioactive ore for sale here or elsewhere on the internet. Things that are deemed safe or unsafe in regard to standard practices or amounts of nuclear radiation exposure are reasonably solid concepts. In many cases, however, perspectives to do with a person’s personal safety index about radioactive ore and radiation levels can quickly make it a very relative or subjective topic.

Perspectives of Radioactive Ore Safety

For example, when one compares activity or energy output levels of a rock for sale, here, to many of those of man-made isotopes used in science and industry, it will often put even a very safety-conscious person more at ease. Cobalt-60 (used to sterilize instruments or irradiate tumors) emits gamma rays with energies of up to 1.332 MeV, whereas a rock we sell from the floor of Jurassic Canyon is made up primarily of inert stone, marbled with a minority of uraninite which, even in its purest form, emits gamma rays of 2.0 KeV (which, on the same scale as Cobalt-60, above, is only 0.000002 MeV).

Conversely, when someone says they sell “probably the most radioactive natural ore available, period” it gives a different impression to the lay observer, garnering letters of complaint to eBay and revisions to their list of blacklisted materials to now include autunite ore (natural calcium uranyl phosphate formations).

Make no mistake: even natural, 100% unprocessed geological formations in their raw form can be dangerous if mishandled – but this is no different than many substances or objects we take for granted in our daily lives, made available for cleaning, repairs, artwork, or even leisure. The specific precautions and risks may be different, but “how dangerous” these things are, when handled and stored properly, need not be viewed as any differently than a plastic bag (deadly around a toddler unattended), medicines or dietary supplements (often flavored like candy), or an endless list of substances or tools.

Legal Disclaimer (btw, in passing)

We neither claim to be qualified, nor do we assume any responsibility whatsoever, to educate the buyer or possessor of radioactive ore in the necessary topics of safety around the materials nor proper handing nor keeping of them. Below may not be a complete list of adequate resources. It is said person’s own responsibility to seek out and learn the necessary information before acquiring or handling radioactive ore. Below are a number or relevant thoughts and helpful resources.

Inverse Square Law of Radiation and Distance

radiation and distance
Observing the Inverse Square Law of Radiation and Distance: This is often expressed as the Inverse Square Law of Light (or even radio waves), as the same holds true for electromagnetic emissions as it does for nuclear radiation. As an emission travels further away from its source, it spreads out over a greater and greater distance so, the further away you measure it from a single point (or even over a constant surface area as with a 3cm diameter Geiger Mueller probe window facing the course) the lower that energy measurement will be, and predictably so. Specifically, this law states that intensity of a ray or beam is inversely proportional to the square of the distance from a source. This means the radiation levels detected escaping a metal box containing rocks, at 5 meters away, should be far less than merely 5 times less than they are at 1 meter away. The difference is exponential, making additional meter a more effective buffer than the one before it. You may read more about it here, at Open Oregon Educational Resources, where there are other good reads, as well: https://openoregon.pressbooks.pub/radsafety130/chapter/inverse-square-law/

Other Considerations

  • Shielding, the denser the more effective, is an elementary matter (essentially of common sense) but it is highly advised to keep a decent radiation meter of some kind on hand to double check the efficacy of any container at shielding radiation. It is always advised to use the Inverse Square Law of Radiation and Distance in conjunction with effective shielding. The author uses several concentric steel tins within tins to keep a small quantity of ore up in his closet, meters away from any living thing in passing and many meters away from long-term stations such as a bed or desk.
  • Radon gas, a radioactive gas and cancer risk at considerable levels) is emitted by uranium and thorium ores and the sister elements they contain. A few, small rocks is generally of no concern where some semblance of ventilation is present via the opening and closing of doors on a regular basis. Larger amounts no educator or hobbyists normally needs can and will emit enough radon gas to cause concern. Radon gas decomposes and so is only so residual, but enough can be dangerous, especially long-term. Ultimately a radon gas detector is advised if in any doubt whatsoever. The EPA states, “The average indoor radon level is estimated to be about 1.3 pCi/L, and about 0.4 pCi/L of radon is normally found in the outside air. The U.S. Congress has set a long-term goal that indoor radon levels be no more than outdoor levels”.

For about $170 you can buy a detector in the form of a small cube that logs records and sends reports to your smartphone. It can be found at:

  • Some ore can be soft or brittle and great care should be taken not to contaminate areas with it, to ingest it or even inhale tiny particles somehow launched into the air. Fortunately, particles tend to be relatively heavy and do not generally remain airborne for long like average dust, but a sweep of your air conditioner intake filter is also a good check.
  • Pets, children, and any animal or person without adequate judgment or education must 100% effectively be kept away from access to radioactive ore. Contact emergency medical or veterinary professionals if even the slightest doubt exists there could be any issue such as internalizing any quantity of radioactive ore.

This is only a sample list of precautions and considerations.


Since these resources almost invariably involve much more hazardous materials than you will likely ever own, they are a good path to pursue to ensure you take more than ample steps to ensure the safety of you and anyone actively or passively involved with your possession of radioactive ore.

At the time this article was written the University of Washington was offering free courses in safety around radioactive sources such as this general one for lab techs:

and this one which is uranium-specific:

EdApp has a free course available here:

Radiation Safety Institute of Canada has a free course in audio-visial format accomanied by a PDF document (which is good, alone) at:

Internation Atomic Energy Agency (IAEE)
(easy to remember, because when you are at risk of exposure, you may scream, “AIEEeeeee!” and run away)

This is last but most certainly not least in terms of a phenomenal, world resource on radiation safety:

For more, search (as with Google.com) “free course on safety with radioactive materials”.

Honorable mention:

Actually, honorable mention should also go out to the US Nuclear Regulatory Commission (NRC) as their helpful documents often come up as educational materials available online, making nuclear science accessible to the lay person. Also, if you can wait to be contacted back, aren’t bad at answering questions or pointing people in the right direction in terms of legality on a federal level.


They are whose laws allow nationwide possession of radioactive ore (residential/business idiosyncrasies or building codes etc. not withstanding) whereas anything even remotely processed (which includes tailings or floor sweepings from a mine or factory, regardless of if it’s just monazite etc. – this means it was processed and is now “Source Material”!) is subject to state laws in 38 Agreement States whose local regulations trump NRC’s federal codes on anything other than unprocessed ore. This makes things like NRC § 40.22 “Small quantities of source material” completely useless to you on a state level in all 38 Agreement States. Learn the real facts about your state and do not rely on federal laws which do not pertain to you. Fortunately, this is of no consequence in matters of truly unprocessed, raw, radioactive ore which is legal on a federal level that takes precedence over most local regulations.

Is SETI@Home Dead?

If you’re like us you may be wondering, “Is SETI@Home Dead?”. If you closely followed SETI (Search for Extraterrestrial Intelligence) and their volunteer program allowing everyday people to aid in the search for alien radio signals remotely, then you knew that, in March 2020, front end-user participation came to an abrupt stop after 20 years, and you wouldn’t be able to play along anymore. Others come back after their own hiatus (after giving their computers a break from intense background use, or winding up with a new spare) only to find the SETI@Home program isn’t currently available, sadly searching why.

Is it gone for good?



In 1999 SETI made free software available for download to at-home users all over the world, through University of California, Berkeley. This allowed SETI to break free of the constraints of limited computing power, crowd-sourcing more than they could afford or support in-house. Everyday folks could use their spare computing power to help analyze radio telescope data acquired from the likes of the Aricebo Observatory and distributed to them in bite-size blocks for their own computers to chew on at home, looking for potential signs of alien radio transmissions. After the data was sifted through, results were uploaded back to SETI@Home headquarters.

As the Atlantic put it, astronomers “deputized” internet users to help find extraterrestrial signals. I can personally attest to it having been an extremely exciting, free activity in which to initially participate, and to which I’d occasionally return for two decades. Reasons for down time included mitigating extra strain on a computer I was trying to get maximum use out of, and reasons for returning included realizing I had a spare knockabout box to dedicate to the cause. At one point I got space game squad-mates from Jumpgate to participate as a team.

What Happened?

I, the author, for example, had been away from SETI@Home for several years, preoccupied as I often was in-between volunteering CPU/GPU hours. I returned with revitalized zeal to see it running again (and had a spare, expendable PC turn up to dedicate once again) only to discover new blocks of data are no longer being distributed – and haven’t been for some time. Compounding the let-down confusion were numerous, prevalent SETI@Home and Berkeley center-stage pages like “Participate” and “Join” still not being updated to reflect the change to this day, 2 years after the close. I’d re-installed the client BOINC (the client portion of the platform that fueled the program for most of its days)  only to find SETI@Home not available as a program to activate with the software. Adding to the confusion was that, even 2 years later, certain, prominent webpages of the project like Participate  aren’t updated and still instruct you to go ahead. It’s easy to follow them straight from Google and miss a small notice it’s in vain.


The number crunching we users did for SETI@Home was a Phase I tier of the analysis, preparing it for subsequent analyses. They’ve stated that they have enough data having completed that stage for now, and subsequent stages of analysis don’t appear to be considered for crowd-souring in the same manner. Anecdotal reasons stated by general, 3rd-party media keep citing reasons like the limited bandwidth of private internet connections, but that doesn’t satisfy questions about why it was practical to dole phase 1 out to us beginning back in 28 kbps dialup days as bulk, “crude oil” data, yet 80,000 kbps is now too slow to dole the subsequent barrels of clean oil for refinement into gasoline. It all makes perfect sense on their end but the average article pokes around with anecdotes that don’t add up by themselves. Journalists repeat how internet speed is limited compared to drawing it off the archives directly in-house. Journalists repeat how the raw data was shipped physically on tapes and then disk drives from Arecibo to the US instead of trying to do it online. In the end, it appears latter-phase crunching is something they feel is more efficient to run in-house, sitting on 20 years of Phase 1 data directly, instead of doling it out all over again.

One thing they do talk about is an extremely complex and probably ever-changing set of criteria being used as filter parameters. From insane noise and interference removal processes, to potentially rectifying frequency-skewing doppler shift effects of bodies in motion, and much, much more, the latter stages of the data refinement are incomprehensibly extensive and convoluted. It’s probably too much to try to narrow down to client updates as it is constantly modified, as the science is tweaked regularly.

Is SETI@Home Dead or What?

Is it gone for good or in hibernation?

As of right now there is no update on whether of not front end-users of SETI@Home will be treated with data blocks to crunch once again or not. One of the biggest variables is how interesting the subsequent “Nebula” analyses of 20 years of the phase 1 data truly is. Nebula is the name of the back-end software being used to further crunch the front-end SETI@Home crowd-sourced results (as well as some other data such as from another front-end source called SERENDIP or “Search for Extraterrestrial Radio Emissions from Nearby Developed Intelligent Populations”). Nebula appears to be available for download on places like SourceForge, but it’s not some user-friendly thing for the general public like SETI@Home. It requires substantial hardware just to house the database and would be most approachable to set up and run with ample computer science experience. It’s currently being run on the Atlas supercomputer cluster at Einstein@home.

When I asked if SETI@Home was expected to fire back up for remote use some day, veteran participant “Wiggo”, who racked up an estimated 289,427 hours of CPU time running SETI@Home out of Australia between Jan. 2000 and March 2020 replied, “Some of us are waiting in the hope that Nebula will result in findings that will kick things off again with better tuned processes.”

The crowd-sourcing platform BOINC that powered SETI@Home is not only, still available for download, but is going strong allowing at-home volunteers lend computing power to different projects, seeking advancement in fields like biochemistry and medicine.

SETI signal

What is metrical structure ?

While the term “metrical structure” sounds pretty tech-y, it’s less so than it may look. The term metrical structure is specifically associated with a sort of gate or defining arrangement in music and poetry. It is not generally used in most sciences. For example: “prose” is defined as writing that contains no metrical structure (vs. poetry), but we do not refer to the metrical structure of quickly repeating radio astronomical signals.

The following limerick demonstrates the troubled nature of that author’s state of mind:

Metric or Metrical Musings
by Geoff Burroughs

Metrical structure may be used poetically,
in technically-oriented blogs,
but if it’s not really technical
(technically it’s not technical)
Are pulsar pulses structured metrically?

metrical structure

Python versus Matlab: an Unbiased Look

When comparing Python versus Matlab, the very first resources you’ll find are their own special interest groups pushing their own, inevitable favorite in each case (big surprise). Here, without attempting to glorify apples over oranges, let’s just go over key highlights of each, so you know which is best for you.

Python vs. Matlab

What They Have in Common

Both Python and Matlab provide beginner-friendly environments suitable for learning to program. Both are relatively easy with which to become productive rather quickly. Both have a well-established foundation of support and resources, and still have a future ahead of them.

How They Differ

Cost :

One make-or-break, deciding factor of Python vs. Matlab can be money. Python is an open-source, free programming language with supportive elements that can enable someone to finish entire projects without spending a penny on anything but their computer and electricity.

And Matlab isn’t just “proprietary” – even many small companies decide its licensing is prohibitively expensive. That said, while this factor may be a deal-breaker for some, it’s sure to be a non-issue for others with either ample financing or existing access to the Matlab platform at school or work.

Uses :

Python is a general-purpose language with extremely diverse functionality that can can be applied to myriad genres of projects and countless facets thereof. While both Python and Matlab boast sizable libraries to avoid re-inventing the wheel, Python’s are considerably more vast in both number and scope. If you want your first (or next) language to make you the most valuable but aren’t sure exactly how it will be applied, Python would win this round of Python vs. Matlab. In addition to having a wide range of uses, Python is also available on countless operating systems and devices. Matlab boasts being usable on over 1000 common devices, but Python can thrown into virtually any arena in which you either intend to directly work, or even those in which you hope to have your finished product expand and wind up.

Matlab, on the other hand, is a much more specialized platform. Its purpose and functionality is centered more around math and technical computing. This can make it a formidable opponent if you know what you want and that thing is algorithms, big data, analysis, modeling economic data, and countless engineering applications. Matlab has things like Simulink for code-free, block-style model-based design that can run simulations. What’s more, Matlab can be integrated with other languages, like C, C++, Java, .NET and Python, anyway. So if you have the right things in mind such as these, for which Matlab is specifically cut out then it, too, can win a round in the Python vs. Matlab face-off.

In Conclusion

If you’re still considering Matlab after what you’ve seen here, but you’re undecided, chances are it would be beneficial for you to have more than one language under your belt in the long run, anyway. If you’re on the fence and you’re not sure where you’re headed, you could always start out with highly readable and versatile Python and keep your specialty options open for Matlab. Then you could even integrate the two.