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(edited) Transcript for Environmental Sensor Hack Chat part 2

A event log for Environmental Sensor Hack Chat

Radu Motisan will be joining us in the Hack Chat to talk about his environmental sensor project, the uRad detector!

sophi-kravitzSophi Kravitz 09/07/2018 at 20:030 Comments

Radu Motisan3:43 PM

I'll try not to post many links, not to move you guys out of this window too often

pop133:44 PM
Thanks

Radu Motisan3:44 PM
so on a CCD you'll see random pictures in total darkness

Radu Motisan3:44 PM
pixels*

Radu Motisan3:45 PM
again , sorry for the typos, I did about 1000km today, going home from sunny Greece

Radu Motisan3:45 PM
love to talk about ionising radiation after all the UV exposure I got (on those nice beaches hehe)

lol

Radu Motisan3:45 PM
so choosing the sensor can be an issue due to costs

victor.aprea3:46 PM
jealous, i'm half Greek and have never been to Greece!

Radu Motisan3:46 PM
@victor.aprea :)

Radu Motisan3:46 PM
with a mobile phone, you'll be able to see high doses

Radu Motisan3:46 PM
like in my video

Radu Motisan3:47 PM
I used an x-ray source to generate those pixels

Radu Motisan3:47 PM
on small distances I think not more than 2 meters

Radu Motisan3:47 PM
with a source emitting up to  50keV if I recall

Radu Motisan3:48 PM
you would just need some black tape to obscure your camera

Radu Motisan3:48 PM
then have an app that opens the camera and counts the non-black pixels

Dusan Petrovic3:48 PM
Hello from Belgrade @Radu Motisan !

Radu Motisan3:49 PM
@Dusan Petrovic hi there! I just passed through Vrsac , almost home

Radu Motisan3:50 PM
Radon is a concern

Radu Motisan3:50 PM
sadly no uRADMonitor unit detects this gas

Radu Motisan3:50 PM
you get to inhale it , it was a very short half-life, and when it degrades emits alpha radiation

Radu Motisan3:51 PM
that is on on skin, dead cells will stop it like paper does

Radu Motisan3:51 PM
but inside the lungs it bombards unprotected vulnerable cells, inducing mutations

Rebecca E. Skinner3:51 PM
Is radon a practical danger, unless you're in an underground area w exposure to off-gassing from the soil ?

Radu Motisan3:52 PM
I don't think so . I can't think of other sources than soil off-gassing, also including underground waters

Radu Motisan3:52 PM
but this one scenario is more than enough

victor.aprea3:53 PM
people make an issue of it when buying new homes to have the basement checked (but that probably depends on where you are in the world)

pop133:53 PM
I know of a place in Hungary where the thermal water contains radon

Radu Motisan3:54 PM
@pop13  yes, this is common . People used to drink radon rich waters, but also water with radium minerals dissolved

Radu Motisan3:54 PM
until the dangers were understood better

Radu Motisan3:55 PM
@victor.aprea yes, this is a good choice, especially in the more affected areas

Radu Motisan3:55 PM
in Romania we have several uranium mines

pop133:55 PM
An they still drink...

Radu Motisan3:55 PM
there are waters in the valleys where the mines are (mostly in the mountains)

pop133:55 PM
Its available to the public actually

Radu Motisan3:56 PM
people not only use water from wells, but they also build their houses and roads with rocks from local sources

victor.aprea3:56 PM
most of the time testing radon involves putting a thing in your basement for a prescribed period of time under prescribed conditions and then sending the unit off to some lab to be evaluated

Radu Motisan3:56 PM
so a test there revealed concerning levels

Radu Motisan3:56 PM
@victor.aprea yes, and this has to do with the type of detector used for radon

victor.aprea3:56 PM
i've often wondered whether there was a market for a continuous radon monitor

victor.aprea3:57 PM
or whether that was even practically possible

Radu Motisan3:57 PM
it is a ionisation chamber, similar with the geiger tube , but an open enclosure with the electrodes at a lower voltage (about 50V compared to geiger tubes that run at 400-900V)

Radu Motisan3:57 PM
there is

Radu Motisan3:57 PM
the problem is the sensor

Radu Motisan3:57 PM
you want one that is calibrated and will keep its calibration with minimum maintenance

victor.aprea3:58 PM
gotcha

Radu Motisan3:58 PM
you also want a higher volume chamber for increased sensitivity

Radu Motisan3:58 PM
the time you need to keep the "thing" in the basement is also due to the low sensitivity

victor.aprea3:58 PM
sure, ya i know all about calibration :)

Radu Motisan3:58 PM
sensitivity is nothing but the time integration

victor.aprea3:58 PM
oh that is interesting

Radu Motisan3:58 PM
yes, let's take an example

Radu Motisan3:59 PM
you can have a detector tube of 1ml volume

Radu Motisan3:59 PM
and another one of 10ml

Radu Motisan3:59 PM
the internal electrodes are also sized to match

Radu Motisan4:00 PM
you expose them in the same radiation field to the same dose

Radu Motisan4:00 PM
what will you see?

Radu Motisan4:00 PM
right

Radu Motisan4:00 PM
and hits in this case are counts per minute

Radu Motisan4:00 PM
here the time component comes into play

Radu Motisan4:01 PM
you can use either of them to measure the field

Radu Motisan4:01 PM
just your time base will be different

Radu Motisan4:01 PM
and this is important when you have very little time

victor.aprea4:01 PM
makes sense

Radu Motisan4:01 PM
like when you are on the move

Radu Motisan4:01 PM
if you want to scan an area from a helicopter, you'll need big volume detectors

Radu Motisan4:02 PM
like for uranium prospecting

Or for airport security purposes

Radu Motisan4:02 PM
else you'll miss the small variations, if not enough is available, and radon monitoring is about small doses

thank you so much @Radu Motisan !

Radu Motisan4:03 PM
@Sophi Kravitz thanks Sophi!

victor.aprea4:03 PM
later @Sophi Kravitz  cheers

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