Energy From Thorium Discussion Forum

It is currently Nov 22, 2017 5:45 am

All times are UTC - 6 hours [ DST ]




Post new topic Reply to topic  [ 18 posts ]  Go to page Previous  1, 2
Author Message
PostPosted: Feb 26, 2015 12:53 am 
Offline

Joined: Jun 05, 2011 6:59 pm
Posts: 1337
Location: NoOPWA
Cyril R wrote:
Ok I think I understand this ground shielding effect. It has to do with line of sight over the virtual sphere of the target vs. source. If the target is in the air it will see a lot of radiation as it has a wide LOS, if it is on the ground it has a limited LOS to cesium that is further away.

So are you saying that the peak values for a person standing upright on the ground are not around 2 mSv/day but actually 0.7 mSv/day?

The last comparison I read about Fukushima groundshine from proper measurements versus airborne measurments showed proper measurements between 1/3 and 1/7 the airborne. So the proper readings would be somewhere between 0.3 and 0.7 rather than 2. By the way, 2mSv/day is quite a bit higher than most measurements. You have to be very close to the plant boundary to get near that.

_________________
DRJ : Engineer - NAVSEA : (Retired)


Top
 Profile  
 
PostPosted: Feb 26, 2015 1:33 pm 
Offline

Joined: Jul 14, 2008 3:12 pm
Posts: 5058
Very close to the plant boundary... Kiteman may be right! Here's a website that has real time monitoring of the dose at the fence

http://www.tepco.co.jp/en/nu/fukushima- ... dex-e.html

Below 4 microsierts/hour, about 20x below the threshold level for health damage from chronic radiation!

To get above it requires that you stand right next to the reactor buildings on the site itself, at around 100 microsieverts/hour. Amazingly that level is only slightly above the supposed threshold for health damage.

Amazing. They have been doing a good job at cleaning up the site.


Top
 Profile  
 
PostPosted: Mar 01, 2015 2:37 am 
Offline

Joined: Jun 05, 2011 6:59 pm
Posts: 1337
Location: NoOPWA
Cyril R wrote:
Very close to the plant boundary... Kiteman may be right! Here's a website that has real time monitoring of the dose at the fence

To get above it requires that you stand right next to the reactor buildings on the site itself, at around 100 microsieverts/hour. Amazingly that level is only slightly above the supposed threshold for health damage.

Amazing. They have been doing a good job at cleaning up the site.
Actually, I believe the temporary post that reads 100µSv/hr is at the bottom of the ramp down to lower lever. Last I saw, the levels actually around the buildings were still in the mSv/hr range. But that was the middle of last year IIRC.

_________________
DRJ : Engineer - NAVSEA : (Retired)


Top
 Profile  
 
Display posts from previous:  Sort by  
Post new topic Reply to topic  [ 18 posts ]  Go to page Previous  1, 2

All times are UTC - 6 hours [ DST ]


Who is online

Users browsing this forum: No registered users and 1 guest


You cannot post new topics in this forum
You cannot reply to topics in this forum
You cannot edit your posts in this forum
You cannot delete your posts in this forum
You cannot post attachments in this forum

Search for:
Jump to:  
cron
Powered by phpBB® Forum Software © phpBB Group