# Presentation: 472931

## Ten Principles and Ten Commandments of Radiation Protection

**Ten Principles ****and Ten Commandments ****of Radiation Protection**

- Daniel J. Strom
- Paul S. Stansbury

- _[strom@pnl.gov](mailto:strom@pnl.gov)_
- _[paul.stansbury@pnl.gov](mailto:paul.stansbury@pnl.gov)__ _
- Battelle

## This Presentation Focuses on the First of Three Radiological Protection Functions

- Keep it safe
- prevent tissue (deterministic) effects
- limit probability of stochastic effects
- Keep it legal
- keep it affordable
- be able to prove it
- Help people feel safe
- create peace of mind

- Strom & Stansbury

## Overview of 10 Principles and 10 Commandments

- Overview of 10 Principles and 10 Commandments

- External irradiation, intakes, “ontakes”
- Principles: what’s going on
- Commandments: what to do
- Application based on knowledge of radiological situation

- Strom & Stansbury

**Notes:**
For decades, the phrase "time, distance, and shielding" has been presented as summarizing the "basics" of radiation protection. 
Indeed, for protection from external radiation sources, these three principles are probably the most important ones on which a worker can make decisions and take actions.  

However, these principles do not address protection against intakes of radioactive materials or "ontakes" (skin contamination), other risk-limiting measures, or other important protective measures taken by governments, public health agencies, regulators, and institutional programs.
Performance standards, health education, facility engineering requirements, and administrative procedures.

Furthermore, "time, distance, and shielding" simply do not apply to many radiation protection situations, such as indoor radon.  And finally, the standard liturgy of "time, distance, and shielding" doesn't tell the worker what action to take.  For these reasons, I have chosen to separate the principles (short names) from the commandments (what to do).

## Sources, Exposures, Intakes & Ontakes, and Irradiation

- Strom & Stansbury

##       Source        Exposure                   Intake                      Irradiation          

-       Source        Exposure                   Intake                      Irradiation

- Strom & Stansbury

##       Source        Exposure                   Intake                      Irradiation          

-       Source        Exposure                   Intake                      Irradiation

- Strom & Stansbury

## Any place you can intervene on an arrow, you can do radiation protection.

- Strom & Stansbury

## 1.  Time

- Hurry (but don’t be hasty)
- Minimize exposure or intake time
- Manage total dose by managing time

- Strom & Stansbury

**Notes:**
External irradiation

Intakes and ontakes

## How Radiation Dose Depends on Time

- External Irradiation: *dose* = *(dose rate) **×** (time)*
- Internal Irradiation: *dose ** intake*
*intake *(via inhalation) =
*(airborne concentration) **× (breathing rate)** **× (time)*
- (          Bq/m3                ) × (     m3/hour    ) × (hours)
*intake *(via ingestion) =
*(food/drink concentration) **× (ingestion rate)** **× (time)*
- (               Bq/kg              ) × (      kg/day     ) × (days)

- Strom & Stansbury

**Notes:**
External irradiation

Intakes and ontakes

## Time: Plan to Avoid Intakes and Irradiation

- Don’t wait or linger in
- elevated radiation areas
- airborne radioactivity areas
- contaminated areas
- Practice and rehearse “hot” jobs
*Promptly *evacuate when needed
- sheltering may be preferable, however

- Strom & Stansbury

**Notes:**
External irradiation

Intakes and ontakes

## 2.  Distance	

- 2.  Distance

- Stay away from it or stay upwind
- Maximize distance
- Understand the “inverse square law”
- never pick a strong source up with your hand

- Strom & Stansbury

**Notes:**
Works for 
- external irradiation 
- sources of airborne or waterborne activity
Work practices
Evacuation

## Never touch a

**Never touch a**
**highly **
**radioactive**
**source**

- Strom & Stansbury

## Dose Rate Decreases with Increasing Distance	 from a Source

- Dose Rate Decreases with Increasing Distance	 from a Source

- Evacuation can increase distance
- Distance can also increase source barrier (shielding)

- Strom & Stansbury

**Notes:**
Works for 
- external irradiation 
- sources of airborne or waterborne activity
Work practices
Evacuation

## Distance: Stay upwind

- Artificial wind: ventilation
- Fume hood
- Negative pressure rooms
- Natural wind can protect from
- Fire
- “Broken Arrow”
- Radiological Dispersion Event
- Nuclear Explosive

- Strom & Stansbury

**Notes:**
Works for 
- external irradiation 
- sources of airborne or waterborne activity
Work practices
Evacuation

## 3.  Dispersal

- Disperse it and dilute it
- “The solution to pollution is dilution”
- Minimize concentration, maximize dilution

- Strom & Stansbury

**Notes:**
Mouth around the exhaust pipe
Irreversible
Cheap
Antithetical to Source Barrier Principle

## Stack for Dispersal

- Strom & Stansbury

## 4.  Source Reduction

- Use as little as possible
- Minimize production and use of radiation and radioactive material
- Clean it up, keep it clean
- Delay (maximize decay)
- Do it now (minimize ingrowth)
- Prevention: criticality, nuclear war

- Strom & Stansbury

**Notes:**
Source: source of radiation or mass of radioactive material

A priori (cheap) vs a posteriori (expensive)

decay: re-entry into target room, nuclear war, spent fuel, Green Run

ingrowth: fuel fabrication Pa-234m in U-238; Rn progeny in mines; Y-90 in Sr-90; Am-241 in Pu.

## Source Reduction: 	Clean it up and keep it clean

- Contamination control can reduce
- external irradiation
- intakes
- ontakes

- Strom & Stansbury

## Source Reduction: 	Delay (maximize decay)

- Stay in fallout shelter
- Wait to enter TMI
- Wait to reprocess irradiated fuel
- Hanford’s 1949 “Green Run” reprocessing of fresh fuel violated this and released 1.8 PBq of 131I
- Delay handling of accelerator targets

- Strom & Stansbury

## Source Reduction: 	Do it now (minimize ingrowth)

- Work soon with newly separated
- 90Sr (to avoid 90Y’s hard )
- uranium (to avoid 234mPa’s hard )
- plutonium (to avoid 60 keV  from 241Am)
- Rush air into and out of an underground mine
- avoid ingrowth of radon (222Rn) and thoron (220Rn) progeny

- Strom & Stansbury

## Source Reduction: 	Prevention

- Changing construction materials
- cobalt in valve seats in nuclear power plants
- Change coolant chemistry in BWR to reduce activation
- Criticality
- Nuclear war

- Strom & Stansbury

## Prevent Use of Nuclear Weapons

- Strom & Stansbury

## There Are Two Kinds of Barriers

- Keep-it-in barriers
- playpen, corral, fence at zoo exhibit
- bag, box, or bottle
- Keep-it-out barriers
- roof
- fortress
- window screen

- Strom & Stansbury

**Notes:**
Shields for sources and reactors are keep-it-in barriers
Shields for detectors and x-ray film storage, and fallout shelters are keep-it-out barriers

A priori (cheap) vs a posteriori (expensive)

decay: re-entry into target room, nuclear war, spent fuel, Green Run

ingrowth: fuel fabrication Pa-234m in U-238; Rn progeny in mines; Y-90 in Sr-90; Am-241 in Pu.

## 5.  Source Barrier

- Keep it in
- Engineered controls
- Maximize absorption (shield)
- Minimize release (contain and confine)
- encapsulation
- coating
- containments
- filtration
- negative pressure ventilation

- Strom & Stansbury

**Notes:**
Barrier: something that stops or slows a flow of matter or energy
2 kinds: keep it out, and keep it in
Keep it in: Engineered Controls
biological shield, tube housing
encapsulation, containments (glove box, fume hood), filtration, ventilation

## Massive Shielding and Containment

- Strom & Stansbury

## Containment Glove Bags

- Strom & Stansbury

## Typical Glove Box Line

- Strom & Stansbury

## Fog Cannon to Suppress Dust

- Strom & Stansbury

## 6.  Personal Barrier

- Keep it out
- Minimize entry into the body of radiation and radioactive materials
- personal protective equipment (PPE)
- lead aprons
- fallout shelters
- mass on space missions

- Strom & Stansbury

## PPE: Personal Protective Equipment“PCs”: Protective Clothing

- Strom & Stansbury

## Personal Barrier: Sheltering

- Fallout shelter
- Buildings, basements
- can have significant effect for radiological, chemical, and biological agents

- Strom & Stansbury

## 7.  Decorporation

- Internal and surface irradiation only
- after intake
- or ontake
- Get it out or off of you
- Maximize removal or blocking of materials from the body
- decontamination
- decorporation

- Strom & Stansbury

**Notes:**
decontamination: washing, debridement, excision
chelation, Prussian blue
forcing fluids
blockers (KI)

## Decontamination: Get it off you

- Changing clothes and shoes will often get rid of 90% of any contamination _**on**_ a body
- Soap, water, and shampoo will get rid of almost all of the rest
- Don’t drop the clothes where you will re-contaminate yourself
- Hold breath while doffing PPE to avoid inhaling resuspended contamination

- Strom & Stansbury

## Decorporation: Get it out of you

- Iodine pills
- 130 mg KI = 100 mg I
- _Only_ good for radioactive iodine.  Useless for any other radionuclide
- Nuclear reactors, nuclear weapon detonations, or radiochemical operations with iodine (123I, 125I, 129I, 131I) are the sources of concern for radioactive iodine
- Diuretics and lots of water helps for 3H2O
- Chelating agents, e.g., Ca-DTPA or Zn-DTPA, can be good for nuclides that deposit in bone
- Prussian blue helps somewhat for cesium (137Cs)
- Surgical removal of objects, debridement of wounds

- Strom & Stansbury

## 8.  Effect Mitigation

- Limit the damage
- Optimize allocation of exposure over time and among persons
- Scavenge free radicals
- Induce repair
- priming dose, adaptive response

- Strom & Stansbury

**Notes:**
there exists no antidote

## Effect Mitigation

- Suppose a task will result in 10 person-Gy
- if 1 person does it, result may be near-term death
- if 3 people do it, result may be acute radiation syndrome followed by elevated risk of cancer
- if 10 people do it, there will be few, if any symptoms
- if 100 people do it, there will be no symptoms
- if 500 people can share the job, it can be done “safely” and within regulatory limits
- Examples:
- recovery of 90Sr RTG in Republic of Georgia
- steam generator repair in nuclear power plant

- Strom & Stansbury

## The Latest Fad in Radiation Protection(The New Yorker, June 30, 1997)

- Strom & Stansbury

## 9.  Optimal Technology

- Choose the best technology
- Optimize the risk-benefit-cost figure
- Non-radiation alternatives

- Strom & Stansbury

**Notes:**
shoe-fitting fluoroscopes
pelvimetry
RIA -- enzyme-linked immunosorbent assay (ELISA), fluorescence immuno assay (FIA)
alternatives to fission or fusion for electricity and propulsion
nuclear weapons: chemical, biological, fuel-air weapons
thorotrast
I-123 or Tc-99m instead of  I-131
fast film-screen combinations
QC on x-ray developer

## Optimal Technology 1

- Pelvimetry (radiography) v. Ultrasound
- Computed Tomography (CT)
- 	v. Magnetic Resonance Imaging (MRI)

- Strom & Stansbury

## Optimal Technology 2

- Radioimmunoassay (RIA) v. enzyme-linked immunosorbent assay (ELISA), fluorescence immunoassay (FIA), stable isotope tracers
- Thorotrast v. other contrast agents
- Fast film-screen combinations
- QC on x-ray developer
- Automatic collimation

- Strom & Stansbury

## Optimal Technology 3

- Shoe-fitting fluoroscopes v. mechanical sizing
- Alternatives to fission, fusion, or decay heat for electricity and propulsion (submarines, spacecraft, ...)
- Nuclear weapons v. conventional, chemical, biological, fuel-air weapons
- Depleted uranium v. tungsten v. lead for shells

- Strom & Stansbury

## Optimal Technology 4: Which “Iodine”?

- 123I
- 125I
- 131I
- 99mTcO4
- pertechnetate ion
- can be used for imaging thyroid, salivary glands, and lactating female breast

- Strom & Stansbury

## 10.  Limit Other Exposures

- Don’t compound risks (don’t smoke)
- Minimize exposures to other agents that may work in concert with radiation
- genotoxic agents
- initiators
- promoters
- tumor progression agents

- Strom & Stansbury

## Which lung is more susceptible to radiation effects?

- Strom & Stansbury

## Limit Other Exposures: Microbes

- Manage infection during hematopoietic, gastrointestinal, and cutaneous radiation syndromes
- antiseptics
- antibiotics
- reverse isolation
- sterile materials

- Strom & Stansbury

## Good radiation protection is simple  . . .

- Know what the hazards are in advance
- Know the path by which a potential hazard will cause harm
- Apply the principle (or commandment) to block the hazard from doing harm

- Strom & Stansbury

## Summary of Principles

- Time
- Distance
- Dispersal
- Source Reduction
- Source Barrier

- Personal Barrier
- Decorporation
- Effect Mitigation
- Optimal Technology
- Limit Other Exposures

- Strom & Stansbury

## Summary of Commandments

- Hurry
- Stay away/upwind
- Disperse and dilute
- Use little
- Keep it in

- Keep it out
- Get it out/off
- Limit damage
- Choose best technology
- Don’t compound risks

- Strom DJ  The Ten Principles and Ten Commandments of Radiation Protection.  *Health Physics* 70(3):388-393; 1996. _[http://qecc.pnl.gov/10Prin.pdf](http://qecc.pnl.gov/10Prin.pdf)__ _
- This presentation can be downloaded from: _[http://www.pnl.gov/bayesian/strom/strompub.htm](http://www.pnl.gov/bayesian/strom/strompub.htm)__ _

- Strom & Stansbury