What we know:
Yesterday, Phoenix’s Beta Counts per Minute was 700
CPM according to radnet
Now let us look at EPA responder guidelines
I. EPA’s Emergency Response Air Monitoring Guidance
Tables 2009 edition
This manual instructs emergency responders to
consult with a health physicist when radiation levels are at 3 times background
The
occupational action level is 300 CPM beta or 10 microsieverts an hour
II. Turnbacks Guidance Final MOU November 2007
Memorandum of Understanding on Radiation Turnback Levels for EPA Personnel
Responding to Radiological Emergencies
[paraphrasing] This documents stipulates that exposure must not
exceed 500 millirem during 1 year.
500millirem is 5 millisieverts of exposure.
In certain emergency conditions, the document states
that workers can be exposed to higher amounts if they sign waivers. Waivers are
deemed necessary because they are assuming risk.
Workers are supposed to turn back at 10 rem per hour
of gamma exposure during the early stages
of an emergency and 1.5 rem an hour during the intermediate phase of an
emergency [end paraphrasing]
Majia here: One hour of 10 rem is 100 millisieverts!
That means emergency responders in these types of emergencies would be
sacrificing their health to assume control of the emergency.
What do we know about cancer risks at various levels
of exposure?
Here is 1 important study I posted about a couple of
weeks ago.
Here is the study and the relevant finding: For
every 10 millisieverts of low-dose ionizing radiation, there was a 3% increase
in the risk of age-and-sex adjusted cancer over a mean follow-up period of 5
year
Cancer risk related to low-dose ionizing
radiation from cardiac imaging in patients after acute myocardial infarction.
By Mark
J. Eisenberg MD MPH, Jonathan Afilalo MD MSc, Patrick R. Lawler MD, Michal
Abrahamowicz PhD, Hugues Richard MSc, Louise Pilote MD MPH PhD http://www.ncbi.nlm.nih.gov/pmc/articles/PMC3050947/pdf/1830430.pdf
[Excerpted] The cumulative exposure to
radiation from cardiac procedures was 5.3 milli Sieverts (mSv) per patient
year, of which 84% occurred during the first year after acute myocardial
infarction. A total of 12 020 incident cancers were diagnosed during the
follow-up period. There was a dose dependent relation between exposure to
radiation from cardiac procedures and subsequent risk of cancer. For every
10 mSv of low-dose ionizing radiation, there was a 3% increase in the risk of
age- and sex-adjusted cancer over a mean follow-up period of five years (hazard
ratio 1.003 per milliSievert, 95% confidence interval 1.002–1.004).
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Radiation
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