Nuclear Energy Safety

1
Nuclear Energy Safety

• Operation, Accidents, Attacks, and Proliferation
• Kallie Metzger

2
Health Concerns

• Radiation Poisoning

3
Radiation Poisoning

• Large dose of radiation in a short amount of time
  
• OR Low level exposure for a long period of time.
• Symptoms occur because it makes you feel nauseas
  and radiation interferes with cell division
• A cell incident to radiation can
• Divide as planned and remain unaffected
• Die- (This is why radiation is used in cancer
  treatment!)
• Or divide incorrectly
• If this is the case, as the mutated cells
  regenerate they create more and more mutated
  cellscancer

4
Continued

• How exposure is measured
• Rad- 0.01 Joules of energy per kilogram of
  tissue.
• (Gy)- 1 joule per kilogram of tissue
• thus, 100 rad1 Gy
• In order to determine the effect of the dose on
  the tissue, you must first know the specific
  radiation types affect on tissue, or relative
  biological effectiveness (RBE), which you
  multiply by the dose to determine the overall
  effect, given in units of Seiverts (100rem1 Sv)
• The RBE is given in units of Röntgen-or rems and
  is called a quality factor and therefore denoted
  by Q.
• Alpha-Q may be as high as 20
• Neutron radiation- depends on their energy.
• Beta particles, x-rays, and gamma rays- Q1

5
Levels of Exposure

• 0.050.2 Sv (520 REM)
• No symptoms---may be beneficial? (hormesis)-
• 50 mSv is the yearly federal limit for radiation
  workers in the United States. In the UK the
  yearly limit for a classified radiation worker is
  20 mSv.
• 0.20.5 Sv (2050 REM)
• No noticeable symptoms. Red blood cell count
  decreases temporarily.
• 0.51 Sv (50100 REM)
• Mild radiation sickness with headache and
  increased risk of infection due to disruption of
  immunity cells. Temporary male sterility is
  possible

6
Continued

• 12 Sv (100200 REM)Light radiation poisoning,
  10 fatality after 30 days
• Typical symptoms include mild to moderate nausea
  (50 probability at 2 Sv), with occasional
  vomiting, beginning 3 - 6 hrs after exposure and
  lasting for up a day.
• Followed by a 10 to 14 day dormant phase, after
  which light symptoms like general illness and
  fatigue appear because immune system depressed.
• Temporary male sterility is common.
• Spontaneous abortion or stillbirth will occur in
  pregnant women.
• 23 Sv (200300 REM)Moderate radiation poisoning,
  35 fatality after 30 days
• Nausea is common (100 ),with 50 risk of
  vomiting symptoms onset at 1 to 6 hours after
  irradiation and last for 1 to 2 days.
• 7 to 14 day latent phase, after which the
  following symptoms appear loss of hair all over
  the body (50 probability), fatigue and general
  illness.
• Massive loss of white blood cells, greatly
  increasing the risk of infection.
• Permanent female sterility is possible.
• 34 Sv (300400 REM)Severe radiation poisoning,
  50 fatality after 30 days
• Symptoms are similar to the 23 Sv dose with
  uncontrollable bleeding in the mouth, under the
  skin and in the kidneys after the latent phase.

7
It gets worse

• 46 Sv (400600 REM)Acute radiation poisoning,
  60 fatality after 30 days
• Fatality increases from 60 at 4.5 Sv to 90 at 6
  Sv (unless there is intense medical care)
• Symptoms start 30 min.- 2 hrs after exposure and
  last up to 2 days.
• 7 to 14 day latent phase, after which generally
  the same symptoms appear as with 3-4 Sv
  irradiation, with increased intensity.
• Female sterility is common at this point.
• The primary causes of death (in general 2 to 12
  weeks after irradiation) are infections and
  internal bleeding.
• 610 Sv (6001,000 REM)Acute radiation poisoning,
  near 100 fatality after 14 days.
• Survival depends on intense medical care.
• Bone marrow is nearly or completely destroyed
  (bone marrow transplant required) Gastric and
  intestinal tissue are severely damaged.
• Symptoms start 15 to 30 minutes after irradiation
  and last up to 2 days.-Latent phase-death-
• Recovery would take several years and probably
  would never be complete.

8
Even Worse

• 1050 Sv (1,0005,000 REM)Acute radiation
  poisoning, 100 fatality after 7 days
• An exposure this high leads to spontaneous
  symptoms after 5 to 30 minutes.
• powerful fatigue and immediate nausea caused by
  direct activation of chemical receptors in the
  brain by the irradiation
• there is a period of several days of comparative
  well-being-latent phase- After that, cell death
  in the gastric and intestinal tissue, causing
  massive diarrhea, intestinal bleeding and loss of
  water/
• This leads to water-electrolyte imbalance. Death
  sets in with delirium and coma due to breakdown
  of circulation. Death is inevitable only
  treatment is pain therapy.
• More than 50 Sv (gt5,000 REM) death
• an operator receiving between 60 and 180 Sv
  (18,000 REM) to his upper body in an accident at
  Los Alamos, New Mexico, USA on in December 1958,
  survived for 36 hours

10-20 Gy
9
So, with all the riskswe need regulations
10
Agencies

• Internationally -International Atomic Energy
  Agency (IAEA)
• U.S.- Civilian nuclear safety is regulated by the
  Nuclear Regulatory Commission (NRC). BUT the
  safety of nuclear plants and materials controlled
  by the U.S. government for research, weapons
  production, and those powering naval vessels, is
  not governed by the NRC.
• UK -Nuclear safety is regulated by the Nuclear
  Installations Inspectorate (NII) and the Defense
  Nuclear Safety Regulator (DNSR).

11
International Atomic Energy Agency (IAEA)

• Est. in 1957 as the worlds Atoms for Peace
  program
• Promote peaceful use of nuclear energy and
  inhibit use for military purposes
• Est. the International Nuclear Events Scale
• 144 member states
• In terms of safety and security, they oversee
  nuclear installations, radioactive sources,
  radioactive materials in transport, and
  radioactive waste.
• A core element is setting and promoting the
  application of international safety standards for
  the management and regulation of activities
  involving nuclear and radioactive
  materials.-IAEA
• The focus is on helping States prevent, detect,
  and respond to terrorist or other malicious acts
  - such as illegal possession, use, transfer, and
  trafficking - and to protect nuclear
  installations and transport against sabotage.-
  IAEA

12
Nuclear Regulatory Commission (NRC)

• Created in 1974
• Regulates commercial nuclear power plants and
  other uses of nuclear materials, such as in
  nuclear medicine, through licensing, inspection
  and enforcement of requirements.
• Their program establishes limits for radiation
  exposure for workers and the general public and
  requires that those using nuclear material take
  steps to keep exposures well below the limits.
• If you want to use radioactive material, you must
  obtain a license. EXCEPT-in the case of very
  small amounts of radioactive materials -- like
  the tiny radiation source inside many smoke
  detectors. BUT the manufacturing of these and
  similar items, require specific licensing and
  regulatory control.
• Licenses Commercial nuclear fuel facilities
  involved in the processing and fabrication of
  uranium ore. Licenses for other uses of
  radioactive materials are issued either by the
  NRC or by State Governments under NRC-approved
  programs.
• Construction permit
• operating license
• Individual personnel licenses- (Reactor Operator
  and Senior Reactor Operator)

13
International Nuclear Events Scale
http//www-ns.iaea.org/tech-areas/emergency/ines.h
tm
14
International Nuclear Events Scale (INES)

• Established by the IAEA
• Level 7
• A large off-site impact, widespread health and
  environmental effects.
• Example Chernobyl disaster (former Soviet
  Union) in Ukraine - 1986.
• Level 6
• Significant off-site release, likely to require
  full implementation of planned countermeasures.
  Example Mayak accident (former Soviet Union) -
  1957. 
• Level 5
• Limited off-site release, likely to require
  partial implementation of planned
  countermeasure-example Windscale fire (1957) or
  severe damage to a reactor core/radiological
  barriers- example Three Mile Island accident
  (1979). 
• Level 4
• Minor off-site impact resulting in public
  exposure of the order of the prescribed limits,
  or
• significant damage to a reactor
  core/radiological barriers or the fatal exposure
  of a worker.
• Examples Sellafield (UK) - 5 incidents 1955 to
  1979, Saint-Laurent Nuclear Power Plant 1980,
  Buenos Aires 1983, and Tokaimura nuclear
  accident (Japan) - 1999. 
• Level 3
• A very small off-site impact, public exposure at
  levels below the prescribed limits, or severe
  spread of contamination on-site and/or acute
  health effects to one or more workers, or it is a
  "near accident" event, when no safety layers are
  remaining. Examples THORP plant Sellafield (UK)
  2005 and
• Paks Nuclear Power Plant - 2003.
• Level 2
• This is an incident with no off-site impact, a
  significant spread of contamination on-site may
  have occurred, or overexposure of a worker, or
  incidents with significant failures in safety
  provisions.
• Ex Forsmark Nuclear Power Plant - Sweeden 2006
• Level 1

15
Nuclear Reactor Accidents

• August 21, 1945 Los Alamos National Laboratory,
  Los Alamos, New Mexico, USA Accidental
  criticality
• Harry K. Daghlian, Jr. dropped a tungsten carbide
  brick onto a plutonium core, inadvertently
  creating a critical mass. Fatally radiated -Died
  9/18/45.
• October 812, 1957 Sellafield, Cumbria, UK
  Windscale Fire. Reactor core fire
• Technicians overheated Windscale Pile No. 1
  because poorly placed temperature sensors
  indicated the reactor was cooling rather than
  heating. The excess heat lead to the failure of a
  nuclear cartridge. The resulting fire burned for
  days, damaging a significant portion of the
  reactor core. About 150 burning fuel cells could
  not be lifted from the core, but operators
  succeeded in removing nearby fuel cells.
• An effort to cool the graphite core with water
  eventually quenched the fire. The reactor had
  released radioactive gases into the surrounding
  countryside, primarily in the form of iodine-131.
  Milk distribution was banned in a
  200-square-mile area around the reactor for
  several weeks. Unlikely harm to humans.
• December 30, 1958 Los Alamos, New Mexico, USA
  Accidental criticality
• A critical mass of a plutonium solution was
  accidentally assembled. A crane operator died of
  acute radiation sickness.
• October 1988 Rocky Flats in Colorado.
• At the nuclear trigger assembly facility at Rocky
  Flats in Colorado, two employees and a D.O.E.
  inspector inhaled radioactive particles, causing
  closure of the plant. Several safety violations
  were cited, including uncalibrated monitors,
  inadequate fire equipment, and groundwater
  contaminated with radioactivity.

16
A few more

• June, 1999 - Shika Nuclear Power Plant- Ishikawa
  Prefecture, Japan- Control rod malfunction-INES
  Level needed
• Incident Operators attempting to insert one
  control rod during an inspection neglected
  procedure and instead withdrew three causing a 15
  minute uncontrolled sustained reaction at the
  number 1 reactor of Shika Nuclear Power Plant.
• Result The Hokuriku Electric Company who owned
  the reactor did not report this incident and
  falsified records, covering it up until March,
  2007.
• April 6, 1993 - Tomsk-7 Siberian Chemical
  Enterprise - Tomsk, Russia - Explosion -INES
  Level 4
• Incident Explosive mechanical failure in a
  reaction vessel. The explosion dislodged the
  concrete lid of the bunker and blew a large hole
  in the roof of the building.
• Result The hole released approximately 6 GBq of
  Pu 239 and 30 TBq of various other radionuclides
  into the environment. The accident exposed 160
  on-site workers and almost 2,000 cleanup workers
  to total doses of up to 50 mSv (the threshold
  limit for radiation workers is 100 mSv per 5
  years).
• September 30, 1999 Reprocessing Facility in
  Tokaimura Japan- Accidental criticality INES
  Level 4
• Incident Workers put uranyl nitrate solution
  containing about 16.6 kg of uranium, which
  exceeded the critical mass, into a precipitation
  tank. The tank was not designed to dissolve this
  type of solution and was not configured to
  prevent eventual criticality. Result Three
  workers were exposed to neutron radiation doses
  in excess of allowable limits. Two died.

17
Chernobyl

• April 26, 1986 Chernobyl Nuclear Plant- Prypiat,
  Ukraine (then USSR) - Power excursion, explosion,
  complete meltdown- INES Level 7
• Incident An uncontrolled power excursion during
  a safety test caused a severe steam explosion,
  meltdown and release of radioactive material.
• Result Approximately fifty fatalities resulted
  from the accident and many more cases of cancer.
  (mostly thyroid) The explosion and combustion of
  the graphite reactor core spread radioactive
  material over much of Europe. 100,000 people were
  evacuated from the areas immediately surrounding
  Chernobyl in addition to 300,000 from the areas
  of heavy fallout in Ukraine, Belarus and Russia.
  An "Exclusion Zone" was created surrounding the
  site encompassing approximately 1,000 mi² (3,000
  km²) and deemed off-limits for human habitation
  for an indefinite period.

18
Chernobyl
19
Recent Accidents

• April 10, 2003 - Paks Nuclear Reactor -Paks,
  Hungary -Fuel damaged - INES Level 3
• Incident fuel rods undergoing cleaning spilled
  fuel pellets the plant.
• Result Boric acid was added to the tank to
  prevent the loose fuel pellets from achieving
  criticality. Ammonia and hydrazine were also
  added to absorb iodine-131.
• April 19, 2005 Thorp Nuclear Fuel Reprocessing
  Plant- Sellafield, UK - Nuclear material leak
  -INES Level 3
• Incident 20 tons of uranium and 160 kilograms
  of plutonium dissolved within 83,000 liters of
  nitric acid leaked from a cracked pipe over
  several months into a stainless steel sump
  chamber.
• Result The partially processed spent fuel was
  drained into holding tanks outside the plant.
• November 2005 Excelons Braidwood Station- -
  Braidwood, Illinois - INES Level needed -Nuclear
  material leak
• Incident Tritium contamination of groundwater
  was discovered at Exelon's Braidwood station.
• Result Groundwater off site remains within
  safe drinking standards though the NRC is
  requiring the plant to correct any problems
  related to the release.
• March 6, 2006 Nuclear Fuel Services Erwin Plant-
  Erwin, Tennessee - Nuclear material leak- INES
  Level needed
• Incident 35 liters of a highly enriched
  uranium solution leaked during transfer.
• Result Seven-month shutdown and a required
  public hearing on the licensing of the plant.
• August, 2007 Clinton, Michigan- Theft of nuclear
  sources

20
Nuclear-Non Proliferation Treaty

• Signers the five Nuclear Weapons States (NWS)
  recognized by the NPT the People's Republic of
  China, France, Russian Federation, the UK, and
  the USA.
• Notable non-signers are Israel, Pakistan, and
  India (the latter two have since tested nuclear
  weapons, while Israel is considered by most to be
  an unacknowledged nuclear weapons state). North
  Korea was once a signatory but withdrew in
  January 2003. The legality of North Korea's
  withdrawal is debatable but as of October 9th,
  2006, North Korea clearly possesses the
  capability to make a nuclear explosive device.

21
Nuclear Proliferation
    Red-  Five "nuclear weapons states" from the
NPT Orange- other know nuclear powers Purple-forme
rly possessed nuclear weapons Blue- at one point
had nuclear power Pink-possess just not widely
adopted Lt. Orange- Suspected of having nuclear
power
22
Questions?