[ RadSafe ] Hot particles on automobile air filters

Sat Jun 25 07:07:12 CDT 2011

Dear Jerry,

I will have a look at this idea which I must say I didnt think of as a possibility, it seems daft to me as there would have to be very high activity of radon daughters on a small dust particle. You can do the sums. I do know about radon and dust, the easiest way is to use one of those air ionisers: the dust collected has a very high alpha activity using a scintillation counter. But the CR39 analysis of the filter from such a ioniser does not show particles but merely more tracks.  The obvious way would be to compare filters from Seattle to Fukushima and from Tokyo. My colleague has done this. He tell me there are 37 times more hot particles on the Fukushima than the Tokyo filters. I take his word for this; I have only seen the Tokyo filter; but I have independently obtained 5 filters directly from Japan from a reporter who bought them from members of the public which are being analysed now and so will let you all know what I find. Interestingly he posted me one of the truck filters from Fukushima so I could do CR39 but it was so radioactive it appears to have failed to make it through the USA mail. At least i assume thats the case: we are tryiing totrack it. I am waiting for some new X-ray film but the CR39 on the Japanese filters is under way.
I wish you guys would do this work. Why is it up to me? It is costly in time and money and no one pays for it. 
Cheers
Chris

-----Original Message-----
From: radsafe-bounces at agni.phys.iit.edu on behalf of gelsg at aol.com
Sent: Sat 25/06/2011 00:01
To: radsafe at agni.phys.iit.edu
Subject: Re: [ RadSafe ] Hot particles on automobile air filters

Just FYI, if that filter had been in place for several months (mine has not been changed for several years), all those radon short-lived daughters that were attached to the dust on the filter would have decayed to the Pb-210/Po-210 longer-lived daughters.  I am not sure exactly what was detected, but radon daughters should not be discarded as a possibility based only on being removed for a few weeks.

Jerry Gels
Cincinnati, OH

-----Original Message-----
From: radbloom at comcast.net
To: The International Radiation Protection (Health Physics) Mailing List <radsafe at health.phys.iit.edu>
Cc: The International Radiation Protection (Health Physics) Mailing List <radsafe at agni.phys.iit.edu>
Sent: Fri, Jun 24, 2011 11:14 am
Subject: Re: [ RadSafe ] Hot particles on automobile air filters

I'm curious about the retention efficiency of iodine vs cesium on these 
ilters.  I know the chemical form of the iodine would affect its 
ollection efficiency, but typically carbon filters, not particulate filters, 
re used to (most efficiently) collect iodine species.  Also, it's noted that 
he filters have been in transit for a long time - is that long compared 
o I-131's 8-day half-life, or just long compared to the radon progenies' 
alf-lives? 

Cindy Bloom  

---- Original Message -----

rom: "Chris Busby" <C.Busby at ulster.ac.uk> 
o: "The International Radiation Protection (Health Physics) Mailing List" 
radsafe at agni.phys.iit.edu>, "The International Radiation Protection (Health 
hysics) Mailing List" <radsafe at agni.phys.iit.edu>, "The International Radiation 
rotection (Health Physics) MailingList" <radsafe at agni.phys.iit.edu> 
ent: Friday, June 24, 2011 9:08:16 AM 
ubject: Re: [ RadSafe ] Hot particles on automobile air filters 

----Original Message----- 
rom: radsafe-bounces at agni.phys.iit.edu on behalf of kmcheng1 at netvigator.com 
ent: Thu 23/06/2011 22:29 
o: The International Radiation Protection (Health Physics) Mailing        List; 
he International Radiation Protection (Health Physics)        MailingList 
ubject: Re: [ RadSafe ] Hot particles on automobile air filters 

 simple demonstration we used to show to junior school students about natural 
adioactivity was to cover the nozzle of a vacuum cleaner with a filter paper, 
urn on the cleaner for 5 to 10 minutes and then put the filter paper in front 
f a GM counter.  There were normally sufficient radon progeny on the filter 
aper to give a significant count rate above the background.  The same would be 
xpected on an automobile air filter shortly after it is taken out of a running 
ngine. 
That is probably nothing new, unless the gamma spectrum shows that there are 
omething else other than radon progeny. 
Clement Cheng 
adiation Health Unit 
epartment of Health 
ong Kong SAR, China 

 ???: "Brennan, Mike  (DOH)" <Mike.Brennan at DOH.WA.GOV> 
 ??: 2011/06/24 ??? ?? 03:29:24 HKT 
 ???: "The International Radiation Protection (Health Physics) MailingList" 
         <radsafe at agni.phys.iit.edu> 
 ??: Re: [ RadSafe ] Hot particles on automobile air filters 

 Ah, so the data is robust enough to share with friends, so they can 
 spread the news worldwide, but not robust enough to expose to 
 potentially critical examination.   

 How very, very, usual. 

 >Sorry, Its not my data and you will have to wait for it to be 
 published. It was meaursed in the USA by a colleague. I do however have 
 my own data and will share it with you in due course. 
 Sincerely 
 Chris 

 Sinecerly 
 Chris 
 _______________________________________________ 
 You are currently subscribed to the RadSafe mailing list 

 Before posting a message to RadSafe be sure to have read and understood 
 the RadSafe rules. These can be found at: 
 http://health.phys.iit.edu/radsaferules.html 

 For information on how to subscribe or unsubscribe and other settings 
 visit: http://health.phys.iit.edu 
 _______________________________________________ 
 You are currently subscribed to the RadSafe mailing list 

 Before posting a message to RadSafe be sure to have read and understood the 
adSafe rules. These can be found at: http://health.phys.iit.edu/radsaferules.html 
> 
 For information on how to subscribe or unsubscribe and other settings visit: 
ttp://health.phys.iit.edu 

_______________________________________________ 
ou are currently subscribed to the RadSafe mailing list 
Before posting a message to RadSafe be sure to have read and understood the 
adSafe rules. These can be found at: http://health.phys.iit.edu/radsaferules.html 

or information on how to subscribe or unsubscribe and other settings visit: 
ttp://health.phys.iit.edu 
But these filters have been across the Pacific and in the mail system for a long 
ime. The gamma spectrum of the filters shows Cs137 and I131. What you say is 
hat the particles in the filters are hot (register as splashes on Xray film) 
ecasue of radon daughters? yes? 
hris 
______________________________________________ 
ou are currently subscribed to the RadSafe mailing list 
Before posting a message to RadSafe be sure to have read and understood the 
adSafe rules. These can be found at: http://health.phys.iit.edu/radsaferules.html 

or information on how to subscribe or unsubscribe and other settings visit: 
ttp://health.phys.iit.edu 
______________________________________________
ou are currently subscribed to the RadSafe mailing list
Before posting a message to RadSafe be sure to have read and understood the 
adSafe rules. These can be found at: http://health.phys.iit.edu/radsaferules.html
For information on how to subscribe or unsubscribe and other settings visit: 
ttp://health.phys.iit.edu

_______________________________________________
You are currently subscribed to the RadSafe mailing list

Before posting a message to RadSafe be sure to have read and understood the RadSafe rules. These can be found at: http://health.phys.iit.edu/radsaferules.html

For information on how to subscribe or unsubscribe and other settings visit: http://health.phys.iit.edu