[ RadSafe ] Regarding Greenpeace calculation of doses from Fukushima

[John Ahlquist]

In my day I found HotSpot to be very useful for an emergency situation.  You got 
a quick estimate to guide your actions which is useful in case of a small 
accident, an explosion involving rad materials, etc.  It can provide a useful 
and quick [several minutes] preliminary answer while NARAC is getting into 
action.  However the HotSpot link itself says

"The HotSpot atmospheric dispersion models are designed for near-surface 
releases, short-range (less than 10 km) dispersion, and short-term (less than 24 
hours) release durations in unobstructed terrain and simple meteorological 
conditions. These models provide a fast and usually conservative means for 
estimation of the radiation effects associated with the atmospheric release of 
radioactive materials."
It is not designed for long term releases from multiple sources over complex 
terrain with complex meteorology.  It is not appropriate for what GreenPeace was 
trying to do.  One would have to check their assumptions, too, because the 
results can be significantly influenced by input assumptions.  

John Ahlquist

Date: Wed, 13 Mar 2013 18:35:17 +0000
From: "Dixon, John E. (CDC/ONDIEH/NCEH)" <gyf7 at cdc.gov>
Subject: Re: [ RadSafe ] Regarding Greenpeace calculation of doses
    from    Fukushima
To: "'The International Radiation Protection (Health Physics) Mailing
    List'"    <radsafe at health.phys.iit.edu>
Message-ID:
    <443B252CFD74854783FFA866594EA93E24384AFF at EMBX-CHAM4.cdc.gov>
Content-Type: text/plain; charset="us-ascii"

The use of the HOTSPOT code would not be appropriate for estimation of doses 
(aka, health effects) from the releases that occurred from the Fukushima 
reactors. The dispersion patterns were far to complex. For example, the wind 
patterns were not in just one direction, but all directions (360 degrees) 
because Japan is an island.

I would also not give Greenpeace much credence on this subject.

I would consult NARAC directly and find out which models (LaGrange based) they 
were asked to run for the kind of information which you seek.

Regards,
John E. Dixon, CHP

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu [mailto:radsafe-bounces at health.phys.iit.edu]
 On Behalf Of Victor Anderson
Sent: Tuesday, March 12, 2013 9:57 PM
To: Mattias.Lantz at physics.uu.se; 'The International Radiation Protection (Health 
Physics) MailingList'
Subject: Re: [ RadSafe ] Regarding Greenpeace calculation of doses from 
Fukushima

Yes,

I have used it a lot.  What do you need to know?

Victor

-----Original Message-----
From: radsafe-bounces at health.phys.iit.edu
[mailto:radsafe-bounces at health.phys.iit.edu] On Behalf Of Lantzelot
Sent: Monday, March 11, 2013 7:22 PM
To: The International Radiation Protection (Health Physics) Mailing List
Subject: [ RadSafe ] Regarding Greenpeace calculation of doses from Fukushima

Is there anybody on the RADSAFE list that has experience with the use of the 
Hotspot code? ( https://narac.llnl.gov/HotSpot/HotSpot.html)

As probably known to most of you Greenpeace grabs whatever media attention they 
can get (succeeding remarkably well in some countries), claiming that the recent 
WHO health effects study on Fukushima is covering up the true dose rates. Once 
again they refer to "independent nuclear expert" Oda Becker, her report after 
using Hotspot is here:
http://www.greenpeace.org/international/Global/international/briefings/nucle
ar/2013/2012_OdaBecker.pdf