Faith-based Radiation Protection Robert L. Dixon Wake Forest University School of Medicine The Pope...

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Transcript of Faith-based Radiation Protection Robert L. Dixon Wake Forest University School of Medicine The Pope...

Faith-based Radiation Faith-based Radiation ProtectionProtectionRobert L. DixonRobert L. Dixon

Wake Forest University School of Wake Forest University School of MedicineMedicine

The Pope of ProtectionThe Pope of Protection

The Ayatollah of Rad Controlla

Radiation Protection guidelines for the General Public have long ago

departed the realm of Science

They also have lost any connection to fundamental logic And in their latest iteration,

almost any citizen can easily recognize that they defy

“common sense”

ICRP has chosen the duck as its animal model for radiation protection,

Eh.

But we can still shoot the

ducks, right?

No problem, we just can’t “nuke” ‘em

In 2003 The ICRP* announced its new plan to also protect animals from radiation

*International Council for Radiation Protection(ICRP)

They have taken on all the trappings of Religion – a set of beliefs that cannot be

either verified or denied – you either believe in them or you don’t

Cost per (hypothetical) Life-year Cost per (hypothetical) Life-year savedsaved11

Radiation Emission Standards for Radiation Emission Standards for Nuclear Power Plants: Nuclear Power Plants: $100 $100 Million/life-yrMillion/life-yr Radionuclide Emission Control at Radionuclide Emission Control at NRC- licensed facilities: NRC- licensed facilities: $2.6 $2.6 Billion/life-yrBillion/life-yrWiden lanes on Rural Roads by 2 Widen lanes on Rural Roads by 2 ft: ft: $120,000/life-yr$120,000/life-yr_______________________________________________1. _______________________________________________1. Tengs et al., Tengs et al., Risk AnalysisRisk Analysis 1515, 369-390, 1995 , 369-390, 1995

What kind of thinking can be responsible for this egregious misallocation of resources?

So where would you put the public’s money?

Thinking Inside the BoxThinking Inside the Box

Lower is always

better in here

rdixon
1. only hazard is radiation2. no coupling between the box and the outside world3. money is no object

I can readily prove that most of you are “inside the box” thinkers

How many of you drove here ALARA?

Driving ALARA*Keep your Speed ALARA

*As Low As Reasonably Achievable

•A definite, proven benefit to you and the public.•Saves on fuel •It seems a “no-brainer”

Driving ALARA would inarguably reduce the risk of death - not only to you, but to

other members of the public in your path .

Hey, It doesn’t apply to driving – just radiation! I’m not driving ALARA (or Miss Daisy)!

ALARA? Sure it’ll cost more, but don’t forget we’re dealing with “deadly radiation” here.

So how does it feel inside that box?

Thinking Inside the Box- you’re not Thinking Inside the Box- you’re not alonealone

Recommends Recommends “evasive action” if a “evasive action” if a solar flare is solar flare is encountered in-encountered in-flight! (0.1- 0.5 flight! (0.1- 0.5 mSv/hr)mSv/hr)Thereby creating much greater risks – collision risk by chaos in air traffic control, fuel starvation by reduced jet engine efficiency at low altitudes, and many more than I have space for…

rdixon
solar flare doubles or triples dose rate

Solar FlareSolar Flare? You’ve got to be ? You’ve got to be kidding!kidding!

Cosmic 0.3 mSv

Internal (K-40) 0.4 mSv

Terrestrial 0.3 mSv

Average Natural Background 3 mSv/yr

Radon 2 mSv

Your girl friend is “hot”

1.5 Mev gammas from K-40

To minimize exposure, try to keep close personal contact ALARA, guys

K-40

Half life = 1.3 Billion years1.3 MeV beta (90%)

High energy gamma ray (1.5 Mev) (10%)

Sure your girl friend is “hot”, but to minimize your exposure keep close personal contact ALARA

Oh boy,

cleanup!

You may see a cemetery, but I see a low level waste dump full

of 40K

Unowho

The Linear Non Threshold (LNT) The Linear Non Threshold (LNT) assumption- a fundamental assumption- a fundamental

tenet of “The Church” tenet of “The Church”

With which “death by coefficient” can be meted out to the frightened

masses without restraint

Some Predictions of LNTSome Predictions of LNT

Despite irradiation of mankind throughout Despite irradiation of mankind throughout his evolutionary development, LNT his evolutionary development, LNT predicts that natural background predicts that natural background radiation is killing people at the rate of radiation is killing people at the rate of one million per year.one million per year.

My personal version is calledMy personal version is called LNT-m.a. LNT-m.a. example example

National Safety CouncilNational Safety Council: In the USA a : In the USA a person dies every 13 min due to a motor person dies every 13 min due to a motor vehicle crashvehicle crash

LNTLNT: Natural background radiation likewise : Natural background radiation likewise kills a person in the USA every 12 min, kills a person in the USA every 12 min,

my ass.

These folks are “most sincerely”

dead

Natural Background in USA- Natural Background in USA- Exclusive of Radon (NCRP #45 & Exclusive of Radon (NCRP #45 &

#94)#94)Atlantic & Gulf Coastal Plain- 1.05 mSv/yr

Middle America- 1.25 mSv/yr

Rocky Mountain Plateau- 1.45 mSv/yr

Denver Colorado- 1.65 mSv/yr

Population-weighted average-1.09 mSv/yr

Average +0.25 mSv/yr = 1.34 mSv/yr

The 1 mSv per yr public dose limit is “Down in the noise”

3.5

4.0 mSv

Avg

Avg +1 mSv

Au contraire – they picked 1 mSv per yearThey evidently don’t believe it’s

safe to live in Denver, CO

Despite the variation in natural background, most locales in the US are below 6 mSv per annum.

So where would logic dictate setting the public dose limit?, perhaps 5 mSv?

But that was after IV or V BEIRS

But the “Lords of Protection” secretly yearned to set it even lower, so they turned to a little trickery to try to accomplish the same thing

With “constraints” they could create a new and even lower “de facto” dose limit

NCRP Report # 116NCRP Report # 116National Council on Radiation ProtectionNational Council on Radiation Protection

Dose Limit for a Member of the General Public:

1 mSv/yr But………There’s a catch – you’re not But………There’s a catch – you’re not supposed to use it unless you conduct supposed to use it unless you conduct an investigation of possible exposure an investigation of possible exposure to other sources (another farce by “the to other sources (another farce by “the Solar Flare Players”-Act I, scene I next Solar Flare Players”-Act I, scene I next frame)frame)

I’m from upstairs, and am conducting an ”NCRP - type” investigation-So where do you live or go after work? Is anybody else irradiating you besides me?

This is my lucky day,

Secret ICRP training campSecret ICRP training camp

Behold! multiple sources!

So how did “the solar players” come up with this idea?

Ach so…..

Public Dose Limit- simplifiedPublic Dose Limit- simplified

Rule two : Now DivideRule two : Now Divide Rule one by 4Rule one by 4

Rule one : 1 mSv/yrRule one : 1 mSv/yr

This “Church” is Ruthless in dealing with This “Church” is Ruthless in dealing with Non-believers! Non-believers!

““Will you confess! …………………………. Will you confess! …………………………. “Mother”“Mother”

Our weapons are fear, surprise, and the risk

coefficient!

Ben Archer, Joel Gray,Bob Dixon, Doug Simpkin

So how did I get involved in this Orwellian world?

We presented our final report to NCRP, and were called before “the Pope” (like Gallileo)

Thou shalt design all thy shielding to ¼ mSv per annum whether thou believest or not, for it is thus “written” in NCRP 116 chapter one, verse

122 But..Zip it!

It is futile to resist

Our reply to NCRP

Source Constraints – An ICRP Source Constraints – An ICRP fantasyfantasy

The Myth of Multiple Sources– The Myth of Multiple Sources– which fails to consider:which fails to consider:

• Most sources do not converge to a single location (short range, inactive at night)

• A given person cannot be in more than one place at a given time

This argument is developed in much greater detail in our paper in published in Radiation Protection Dosimetry(2005),v.115, No. 1-4, pp. 16-22.

1

1

11

1 mSv

This

ICRP SPEED LIMIT source constraints

• Speed limit- 60 mph• but we MUST CONSTRAIN YOU TO 20 mph

since you may own more than one auto, or drive on more than one highway

This logic is closely analogous to that used for “source –constraints” - ignoring simultaneity

Suppose we had “caved in” and accepted 0.25 mSv/yr as a shielding design limit in our NCRP 147 report ?

18-MV Vault---Pb “Upgrade”18-MV Vault---Pb “Upgrade”(1-->>0.25 mSv/y)(1-->>0.25 mSv/y)

1.25 in. Pb1.25 in. Pb

1.5 in. Pb1.5 in. Pb

Primary shieldingPrimary shielding

47,000 lb of Pb47,000 lb of Pb

$47,000 material cost$47,000 material cost

Secondary shieldingSecondary shielding

76,500 lb of PB76,500 lb of PB

$76,500 $76,500

Construction costsConstruction costs for for demolition and restoration of demolition and restoration of vault vault $150,000 $150,000

Grand total Grand total $275,000 $275,000

Estimated costs to “upgrade” the US base of Radiation Therapy Vaults of 6 MV – 18 MV Linear Accelerators in order to meet a

lower dose limit of ¼ mSv.yr-___________________________

Additional shielding thickness 2.5 cm leadMaterial cost of additional lead $115,000 USDConstruction Costs per vault : $150,000 USD Total additional cost per vault: $265,000 USDIf built when publicdose limit was 5 mSv/yr: $385,000 USD

Total estimated cost nationwide: $1 Billion! Total lead required nationwide:8 x 108 kg

It’s going to cost you $250,000 to “upgrade” your vault to 0.25 mSv/yr for a slight (hypothetical) increase in protection for the 5 or so members of the public who work in its immediate vicinityAnd by the way, every pizza parlor,

ice cream shop, home or business in the Denver region will have a higher radiation level than that just outside

your expensive new leaded accelerator walls-

Also, those 5 people will be getting more radiation from natural radioactivity inside

their own bodies than from your accelerator

administrator

Administrator

And since it’s going to take several months for the construction, you’ll have to send your patients to the nearest facility in the next county. I hope they don’t mind (or die as a result of Rx interruption)

Glad to hear you beefed up your room shielding Doc. Who’s gonna pay for it?Why You, of

course

Many developing countries who cannot afford modern medical x-ray equipment, waste their precious resources on shielding to the ICRP suggested “limit” of 1/3 mSv/yr blindly adopted by their regulators.

Predictions if Designing Predictions if Designing Shielding to 0.25 mSv per yearShielding to 0.25 mSv per year

An estimated additional 10An estimated additional 1099 kg (1/2 billion kg (1/2 billion pounds) of lead would be required for medical pounds) of lead would be required for medical x-ray alone (50% of total annual production).x-ray alone (50% of total annual production).

(hypothetical) annual risk from 3/4 mSv/yr 4x10-5

(real) annual risk to2:

metal miners & smelters 56 x 10-5

Construction workers 14 x 10-5

2 Wilson and Crouch, Risk-Benefit Analysis, Harvard 2001.

Still no one from NCRP would engage us in debate, so AAPM and ACR convened a national consensus conference at which all interested parties could participateAll major societies were invited: medical, dental, medical physics, health physics, regulatory bodies, and NCRP

ACR AAPM RSNA SNM HPS ACMP NRC FDA CRCPD ADA ACA

NCRPCONSENSUS!

“ NCRP has concluded that a suitable source control for shielding individuals in uncontrolled areas in or near medical radiation facilities is an effective dose of 1 mSv in any year. “1 mSv.y-1 to the maximally exposed individual in an uncontrolled area will provide adequate protection to the employees and the members of the public that access the uncontrolled areas.

Recent NCRP report series for shielding medical x-ray sources

But the real perpetrator of this nonsense was outside our borders – the ICRP. Dixon receives “frag” order

International Shielding Conference

Madeira Portugal, May 2004

“ALARA” attack profile

JDAM – Los!

Hey Emperor! Time for a reality check from the USA. Those clothes aren’t real and your source constraint concept is fundamentally illogical; plus you don’t know how to apply it.

Mission accomplished

Aug 2006 - ICRP regroups and launches a surprise counterstrike across Atlantic - A “stakeholder” meeting [sponsored by the French nuclear energy agency(NEA)?]

The ICRP, the duck, and your gonadsThe ICRP staged a counterattack in

DC in Aug ’06 – a North American “stakeholder” conference. I was there representing AAPM and ready for them (and their Duck); however, the stake I was holding was wooden, if you get my drift! Your gonads took a beating, however, . There were more .govs than .orgs at this conference (and a few .nuts)

ICRP Source Constraints take a ICRP Source Constraints take a beatingbeating

I had unexpected alliesI had unexpected alliesHere’s one from DOE AAPM

To you from me at the NRC

The oft - heard refrain was: “We don’t understand source constraints, nor do we need them”.

“It is not clear to us (nor apparently to ICRP either) how to apply them in practice”.

The New ICRP Effective Dose paradigm whither the gonads?

Those once-proud doppelgangers, icons of radiation protection for decades (and ritually protected at all costs using all manner of lead accessories), have now been relegated to the “backwater of organs

The new ICRP tissue-weighting factors:

the gonads are dethroned(0.2 → 0.08) and the breasts are uplifted (0.05 → 0.12).”

The gonads are hereby dethroned (0.2 → .08)

And the breasts are uplifted (0.05 → 0.12).”

The gonadal supporters were upset, so Lars-Erik threw them a bone, saying the ICRP still believed in protecting the gonads – but it rang hollow

What ‘bout the duck?

How’re they gonna find enough duck A-bomb survivors to figure risks, Eh?

I guess we’llhave to

“nuke” a bunch of

themThey’re not

gonna like that, Eh?

Two can play this decoy

game

And the “duck” rebellion is already beginning

The ICRP is next- bring it on Lars-

Erik

I later gave the duck call to an NEA conference leader who had admired and coveted it - perhaps with similar future mischief in mind?

An attendee stated that ICRP had chosen “Eurocentric” animals, to which an exasperated Lars-Erik retorted “a duck is a duck is a duck!” At that point, I pulled out my duck call, blew a “triple quack with repeat”, which brought down the house –including Lars-Erik- thereby defusing the situation.

Attempting to increase public protection by forcing the doses allowed from medical X-ray sources to Heroically low levels (10% of natural background)is likely to represent net harm to the patient population (the same public) in terms of both increased healthcare costs as well as increased health risk to individual patients, with no proven benefit whatsoever.

The Conference Rapporteur, Henri Métivier, borrowed from a couple of my PPT “slides” in presenting the final conference summary, including my quote below:

TheTheEndEnd

Oh no! – Solar Flare- I’m outta here!