HKARMS

Lessons Learnt from the Japan Nuclear C i i A S f t P titi ’ P tiCrisis – A Safety Practitioner’s Perspective

Joint Seminar

HKARMS, HKOSHA, IOSH (HK), IMechE- HK Branch, SRSO,

Vincent Ho

23 March 2011 Sponsored by: RCPCE

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Sponsored by: RCPCE

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“I hope from the bottom of my heart that the people will, hand in hand, treat each other with compassion treat each other with compassion

and overcome these difficult times”

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Topics to cover

Events at Fukushima I Basic nuclear physics and reactor designsLessons learned from past major nuclear accidentsCommunication during crisisDiscussion

Presentation materials will be posted at hkarms org

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posted at www.hkarms.org

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Disclaimer

I am not here to debate nuclear power is safe or evil As safety I am not here to debate nuclear power is safe or evil. As safety practitioners, we want to learn from other accidents and draw ideas that can enhance the safety of our systemsInformation here is extracted from public domain and news mediaThe event continues to unfold as we speak, likely that you are better informed than mebetter informed than meI do not believe in conspiracy theory, nor dooms day theoryI am quite optimistic

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Conspiracy theory

11 reactors at FukushimaEarthquake caused by Japan testing nuclear weaponsUSS Reagan made a U-turn because of nuclear blastIsraeli security firm in charge at Fukushima plant prior to disaster advising secret nuclear programdisaster, advising secret nuclear programMajor cover up for lack of safety oversight (???!!!)Use of MOX fuel so they can make nuclear weaponUse of MOX fuel so they can make nuclear weaponAlien or Godzilla attack?

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Fukushima I Play animation file

Before/After phtoo

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A summary over past days at Fukushima IPlay animation file

7777Information is limited because most instrumentation failed

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Before and afterBefore and afterReactor 1: • Mar 14, an explosion damages the reactor building and the primary containment vessel.

Refueling Floor

Eleven workers are injured• Mar 16, Nuclear and Industrial Safety Agency stated 70% of the fuel rods were damaged in

news reports• Mar 19, pressure within the reactor containment vessel appears to be stable

Reactor 2• Partial meltdown is presumed to have occurred. The primary containment vessel may have

been damaged and some radioactivity has vented. Reactor has 548 fuel assemblies, the spent fuel pool has 587

• Mar 16, NISA stated 33% of the fuel rods were damaged• Mar 21, though power is partly restored, engineers discover that they do not have enough of it

to fully run the cooling and pressure systemsto fully run the cooling and pressure systems

Reactor 3• The reactor used MOX, which may produce more toxic radioactivity.• Reactor containment vessel may have been damaged and the spent fuel pool may have

become uncoveredR t h 548 f l bli th t f l l h 514• Reactor has 548 fuel assemblies, the spent fuel pool has 514

Reactor 4• No fuel assemblies in reactor; 548 were removed for maintenance to form part of 1,479 in

spent fuel pools• Spent fuel rods in a water pool may have become exposed to air, emitting radioactive gases

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• An explosion and fire have damaged the building

Mar 22/23 Reactors 3 and 4 restored power to control centre lighting and air ventilation

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Nuclear power plants

Nuclear power plants are designed to control the nuclear chain reaction by slowing down neutrons to the fissile

i l th f l d t t f th l d region, cool the fuel, and to transform the released energy into usable form safelyUranium (U-235) and Plutonium (Pu-239) are the typical Uranium (U 235) and Plutonium (Pu 239) are the typical fuels for nuclear power reactorsNuclear fuel needs moderator and coolant to sustain fission and keep fuel in operating temperature

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Nuclear fission: splitting atoms to extract Nuclear fission: splitting atoms to extract energy E = MC2Play animation file

Energy release in terms of heat and radiation (alpha, beta, gamma)Reaction is self-sustained if enough neutrons are available

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Reaction is self sustained if enough neutrons are availableReactor in cold shutdown means not enough neutrons are produced to sustain further fission by inserting “control rods” – neutron absorbers

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Moderator and coolant

Fissile neutrons are fast neutrons and must be slowed down by y“Moderators” to ensure sustained fission in water reactorsNuclear fuel must be continuously cooled to prevent overheating and unintended criticalityunintended criticalityFuel is depleted when fissile elements are “burned up” or “poisoned”, and becomes “spent fuel”Spent fuel gives out decay heat although not going through fission

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Spent fuel gives out decay heat, although not going through fission

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Spent fuel – sore spot of nuclear powerAbout 1 hour after shutdown decay heat is About 1 hour after shutdown, decay heat is about 1.5% of full powerAfter one year, typical spent fuel generates about 10 Kw/tonne of decay heat about 10 Kw/tonne of decay heat, decreasing to about 1 kW/t after ten yearsRadioactive decay also emits alpha and beta particles and/or gamma ray forming beta particles, and/or gamma ray, forming source of radioactive contaminantsSpent fuel must be continuously cooled and covered with water and can become covered with water and can become “critical”A spent fuel pool can store 5 to 10 years

th f t f l b f i ff it

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worth of spent fuel before removing offsite

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MOX - mixed oxide

A blend of Pu and natural, reprocessed, or depleted UComes from surplus weapons-grade Pu and used fuel, which otherwise would have become nuclear waste – a recycle conceptwould have become nuclear waste a recycle conceptPu is often recycled once as MOX fuel in thermal reactors, and spent MOX fuel is stored as wasteAbout 30 thermal reactors in Europe (Belgium Switzerland Germany About 30 thermal reactors in Europe (Belgium, Switzerland, Germany and France) are using MOX; all required conversion and relicensing if not originally designed to run mixed fuel

R t t l t d difi ti t l d i d d– Reactor control systems may need modification; more control rod is needed– MOX fuel tends to run hotter because of lower thermal conductivity– Significant change in reactor redesigned if use over 50% MOX fuel

13131313If you have weapon grade surplus to start with….

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Common types of nuclear power reactors

Light water reactors (water is the moderator and coolant):– PWR (Pressurized Water Reactors)

BWR (Boiler Water Reactors)– BWR (Boiler Water Reactors)

Other types – GCR (Gas Cooled Reactors)– WWER or VVER (Water Water Energetic Reactors)– RBMK (Graphite Moderated, Boiling Water Cooled Channel Type

Reactors)– CANDU (Canada Deuterium Uranium Reactors)– LMFBR (Liquid Metal Fast breeder Reactors)

14141414We will focus on PWR and BWR

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PWR – Pressurized water reactors

Daya Bay and Lingao nuclear power station, Three Mile IslandCompressed water acts as moderator and coolant receives heat in a closed primary loop, no boiling occurs hereThe heat is transferred to a non-radioactive secondary loop through steam generators

Control rods

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PWR

Dominant Technology in the USAMany designs available, non-standardised Enriched uranium oxide 3%; Zircalloy cladEnriched uranium oxide ~3%; Zircalloy cladNuclear submarines adopt similar technology

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PWR

Safe operating characteristics – but still possibility of core damage due to loss of coolant (LOCA) and other beyond design basis accidentsdesign basis accidentsNegative coefficient of reactivityLow alloy steel pressure vessely pLarge thick containment structure

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PWR - protected by thick “trademark” containment

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BWR – boiling water reactors

Water is converted to steam in the reactor and passed directly to the Water is converted to steam in the reactor and passed directly to the turbine – one loop designWater used is extremely pure with no contaminants to absorb radiationFukushima I and II

1919191919Control rods

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BWR

BWR initially thought unsafe due to heat transfer issues – but proved if pressurised, system becomes stableN ti t t ffi i t f ti it b t t l dNegative temperature coefficient of reactivity but not load-following (steam void increases > reduced reactivity)Enriched uranium oxide fuel ~2.2%Simplified plant – only one circuit; about 33% efficientRadioactivity in the water is very short-lived (mostly N-16, with 7 second half life) the turbine hall is accessible soon after the 7-second half-life), the turbine hall is accessible soon after the reactor is shut down for maintenanceStandardised GE design: BWR-1, BWR-2, …., ABWR

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Development of BWR

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BWR t i t M k I II d IIIBWR containments – Mark I, II and III

Mark I was designed in 1960sM k II d M k III Mark II, and Mark III (newest) are improvementsp o e e sLarger reactor vessel than PWRH th t f l l House the spent fuel pool outside primary containment

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containment

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Typical BWR 3 and 4 reactor with Mark I Typical BWR 3 and 4 reactor with Mark I containment

St l li d li d i l d ll Steel-lined cylindrical drywell surrounded by steel-reinforced concrete contains 12 cm thick Reactor pressure vessel (RPV) and associated cooling equipment

Steel-lined pressure suppression wetwell (torus)to limit pressureto limit pressure

A secondary containment with 1.2–2.4 m of steel-reinforced pre stressed

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reinforced pre-stressed concrete

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Refuelling pool must contain waterPlay animation filePlay animation file

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Nuclear safety – “defense in depth”

Reactor is protected by layers Reactor is protected by layers of safety defenses

Physical safety barriers to contain radiation and provide emergency protection

Functionally redundant cooling Functionally redundant cooling systems with multiple power supplies (offsite, diesel generators batteries)generators, batteries)

Redundant Control and power cables should be physically separated or “fire wrapped

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separated or fire wrapped

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One-minute risk assessmentOne-minute risk assessment

IE MFW AFW EInj

EVENT TREE

Fail Path FrequencyIE MFW AFW EInj

BAD THING.01/YR

SAFE

SAFE

SAFE.1

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Fail Path Frequency

IE MFW AFW Emergency Injection

.01/YR X .1 X .5 X .1 = 5X10-5/YR

UNSAFE STATE

AFWFailure

FAIL

FAULT TREE

.1

• IE = initiating event

• MW= main feedwater water going

ValveFailure

OperatorFailure

PumpFailure

0.5• MW= main feedwater, water going

through primary loop

• About 20 to 30 Initiating events

Test &Maintenance

Unavailability

Failure toStart or STBYFailure Rate

Failureto Run

0.1 0.10.3• Level 1, 2, 3 PRA

• Explicit uncertainty analysis and sensitivity analysis

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Unavailability

0.10.10.1

sensitivity analysis

• Shutdown PRA?!

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Event Tree for a BWR loss of offsite Event Tree for a BWR, loss of offsite power, conditional core damage frequency: 3.6E-5

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BWR

D i ti id t i iti ti t t BWR L f Dominating accident initiating events at BWR: Loss of coolant (LOCA), Loss of offsite power (LOOP), Fires, Flood, Earthquake; each of which can potentially led to core melta qua e; eac o c ca po e a y ed o co e eFunctionally redundant Emergency Core Cooling System (ECCS) and Reactor Core Isolation Cooling (RCIC) system to remove residual heat for the nuclear fuelCore melt frequency is 1 to 2 orders of magnitude lower than PWR but with higher containment failure frequencythan PWR, but with higher containment failure frequency

No plant has experienced all these initiating

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No plant has experienced all these initiating events at the same time

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BWREmergency core cooling System Emergency core cooling System (ECCS)– High Pressure Coolant Injection

System (HPCI)System (HPCI)– Low pressure injection System

(LPCI)Automatic Depressurization System – Automatic Depressurization System (ADS)

Reactor Core Isolation Cooling System (RCIC)System (RCIC)Suppression poolContainment enclosure

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More tolerable to reactor transients, LOCA

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BWR d t PWRBWR compared to PWR

Reactor pressure vessel larger and Reactor pressure vessel larger and operating on lower pressure and temperature, ~70bar and 280 OC

Does not use PWR-style outside containment but have pressure suppression pool

Lower initial investment and lower probability of pipe rupture due to the simpler lower pressure designthe simpler, lower pressure design

Higher operating and maintenance costs

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Despite all efforts, accidents still happen

Although designed with Although designed with multiple layers of defense, accidents have occurred and will occurSevere accidents are

tl lt f h mostly a result of human errors with multiple hardware failures in an hardware failures in an unforgiving situation

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Nuclear accidents- International Nuclear Nuclear accidents- International Nuclear Events Scale

Inspired by the Richter scale for earthquake, the International Nuclear Event Scale (INES) was introduced in 1990 b IAEA i d t bl t i ti f 1990 by IAEA in order to enable prompt communication of safety significance information in case of nuclear accidents7 levels on the INES scale7 levels on the INES scale

– 3 incident-levels – 4 accident-levels

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INES ScaleLevel 7: Major accident - Impact on people and environment. Major release of radio active material with widespread health and environmental effects E g Chernobyl of radio-active -material with widespread health and environmental effects. E.g., Chernobyl disaster

Level 6: Serious accident - Impact on people and environment. Significant release of radioactive material likely to require implementation of planned countermeasures Only release of radioactive material likely to require implementation of planned countermeasures. Only one incident to date: Kyshtym (Soviet Union) 1957

Level 5: Accident with wider consequences - Impact on people and environment Limited release of radioactive material likely to require implementation of some environment Limited release of radioactive material likely to require implementation of some planned countermeasures. Several deaths from radiation. Severe damage to reactor core. Release of large quantities of radioactive material with a high probability of significant public exposure. Examples: Windscale fire (United Kingdom) 1957. Three Mile Island (USA) 1979. First p p ( g ) ( )Chalk River (Canada) 1952

Level 4: Accident with local consequences - Impact on people and environment. Minor release of radioactive material unlikely to result in implementation of

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environment. Minor release of radioactive material unlikely to result in implementation of planned countermeasures other than local food controls. At least one death from radiation. Fuel melt or damage to fuel resulting in more than 0.1% release of core inventory. Release of significant quantities of radioactive material with a high probability of significant public exposure

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Status of nuclear power plants in Fukushima as Status of nuclear power plants in Fukushima as of 10:00 March 22 (Estimated by JAIF)

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World's worst nuclear incidentsLevel 7 Chernobyl, Ukraine, 1986 - explosion and fire in y , , p

operational reactor, fallout over thousands of square kilometres, possible 4,000 cancer cases

L l 6 K ht R i 1957 l i i t t kLevel 6 Kyshtym, Russia, 1957 - explosion in waste tank leading to hundreds of cancer cases, contamination over hundreds of square kilometres

F k hi ILevel 5 Windscale, UK, 1957 - fire in operating reactor,

release of contamination in local area, possible 240 cancer cases

Fukushima I

Level 5 Three Mile Island, US, 1979 - instrument fault leading to large-scale meltdown, severe damage to reactor core

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core

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Three Mile Island

Loss-of-coolant accident (LOCA)

Nuclear fuel overheated Nuclear fuel overheated, cladding ruptured & fuel pellets melted – severe core meltdownmeltdown

PWR Containment intact

No release of massive quantities of radiation to the environment

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Three Mile IslandThree Mile Island

Maintenance worker did not reopen feedwater valve after maintenance, violating procedure and rulePilot-operated relief valve (PORV) stuck open and release pressure, even power to the solenoid valve was cut but power indicator light was blown, no feed back valve actual position

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g pControl centre operators assumed PORV is closed and do not trust other readings. Mindset fixated at training scenariosGroups of people react to and make decisions under stress. Operators were overwhelmed with information, much of it irrelevant, misleading, or incorrectNo instrument to show the level of coolant in the core

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Lessons learnt from TMI

Operator training needed to be improvedOperator training needed to be improvedSharing of industry knowledge needed to be more effectiveFission products don't escape in the real world from strong containmentControl rooms were complex, poorly organized, and did not provide important informationprovide important informationThe consequences of a nuclear accident were less than we thought Precious time was wasted on miscommunication and politics -local, state and national officials and agencies to work together and with the private sector

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and with the private sector

Any similarity to local arrangements?

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Can commercial nuclear power reactor

A nuclear power plant is basically a

Can commercial nuclear power reactor explode like a nuclear weapon?

Play animation filesA nuclear power plant is basically a steam engine using nuclear fission as heat source with slow neutronsCommercial power reactors use lowly Commercial power reactors use lowly 2%-3% enriched fuel and cannot explode like a nuclear weapon; weapon grade Pu is 94%+ and run on fast grade Pu is 94% and run on fast neutronsHowever, hydrogen explosion is possible

– Hydrogen from reaction between Zirconium Hydrogen from reaction between Zirconium (fuel cladding) and steam at high temperature

– Hydrogen from splitting water molecules

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– Venting hydrogen or ignite it before reaching dangerous level

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Chernobyl -RBMK

Graphite moderated, water cooled, but cannot have steam bubbleA USSR design that can run on natural uranium and allow fuel rods to be changed without shutting down

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changed without shutting downDesign focused on accident prevention and mitigation, without full containment

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Chernobyl

During reactor transient and loss of offsite power diesel generator During reactor transient and loss of offsite power, diesel generator takes 60-75 seconds to start one main water coolant pumpThe one minutes is not acceptable to RBMK design that has very high “ iti id ffi i t” ti it i ithi h t ti “positive void coefficient” – reactivity can increase within a short time due to presence of steam bubbleSuggested to use turbine as flywheel to produce power for 45 seconds during coast downTest procedure designed off by plant director, not chief engineer or scientistTest ran by less experience night shift. Nuclear excursion led to power spike. Broken fuel rod prevented insertion of control rodRed hot graphite moderator became fuel source for fire and led to

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Red hot graphite moderator became fuel source for fire and led to hydrogen explosion

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Lessons learnt from Chernobyl

The cost of ensuring the safety of nuclear facilities is significantly The cost of ensuring the safety of nuclear facilities is significantly lower than that of dealing with accident consequencesThe accident has shown the importance of strict compliance with the basic and technical safety principlesDemonstrated the need to establish and support a high-level national emergency response system in case of man-made national emergency response system in case of man made accidentsThe medical services were not equipped to deal with or minimize th di l f l l d id tthe medical consequences of a large-scale man-made accident

Any similarity to local arrangements?

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Any similarity to local arrangements?

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Fukushima Daiichi Nuclear Station

First plant entirely built and operated by TEPCOSix BWR units at the Fukushima Nuclear StationFirst plant entirely built and operated by TEPCOSix BWR units at the Fukushima Nuclear StationUnit 1 is oldest BWR-3/Mark I; initially schedule to shut down after expiry of 40 –year design life but was

d 10 i i F b 2011

Unit 1 is oldest BWR-3/Mark I; initially schedule to shut down after expiry of 40 –year design life but was

d 10 i i F b 2011granted 10-year extension in Feb 2011Units 2-5 are BWR-4/Mark I, Unit 6 is BWR-5/Mark IIU it 1 3 i ti i t t

granted 10-year extension in Feb 2011Units 2-5 are BWR-4/Mark I, Unit 6 is BWR-5/Mark IIU it 1 3 i ti i t tUnit 1-3 were in operation prior to eventUnit 4-6 were in outage prior to eventUnit 1-3 were in operation prior to eventUnit 4-6 were in outage prior to event

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Wh t h d t F k hi IWhat happened at Fukushima I

Designed for a 0.18g peak ground g g p gacceleration (PGA) and a seawall to withstand a 5-m floodAll units performed well at the All units performed well at the Magnitude 7.7 Miyagi earthquake in 1978 with PGA measured at 0.125g for 30 secondsfor 30 secondsSendai earthquake is initially reported to have a PGA of 0.35g near the epicentre ith a 13 m near the epicentre with a 13-m tsunamiUnits 1-3 shut down automatically

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per design

Latest aftershock, 6.6 M yesterday, 6 M this morning

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Ring of fire

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Nuclear power plants in Japan

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Miti ti tiMiti ti tiMitigating actionsMitigating actions

The station was able to deploy portable The station was able to deploy portable generators and utilize a portable pump to inject sea water into the reactor and primary containment

St ti f l i fl di th

generators and utilize a portable pump to inject sea water into the reactor and primary containment

St ti f l i fl di th Station was successful in flooding the primary containment to cool the reactor vessel and debris that may have been released into the primary containment

Station was successful in flooding the primary containment to cool the reactor vessel and debris that may have been released into the primary containmentp y

Boric acid was added to the seawater used for injection. Boric acid is “liquid control rod”. The boron captures neutrons

p y

Boric acid was added to the seawater used for injection. Boric acid is “liquid control rod”. The boron captures neutrons and speeds up the cooling down of the core. Boron also reduces the release of iodine by buffering the containment water pH

and speeds up the cooling down of the core. Boron also reduces the release of iodine by buffering the containment water pH

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water pHwater pH

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Fukushima IFukushima I

Loss of external power (Fukushima II was shutdown), and p ( )depletion of back-up batteries resulted in total loss of pumping to replenish coolant to core and spent fuel poolFukushima I experienced all major risk contributors (LOCA fires Fukushima I experienced all major risk contributors (LOCA, fires, floods, and loss of offsite power accidents, etc.) within hours with earthquake and tsunami being common failure modesNo repair materials and assistance due to collapse of infrastructure, compounded with numerous Magnitude 6+ aftershocksaftershocksPortable generators were used but power supply is insufficient

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Injection of seawater is not a standard operating procedure

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Diesel generator and feedwater pump at Diesel generator and feedwater pump at BWR

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Aftermath

Possible local seawater contamination. Significant long term impact is not likelyFood supply is reported to have a higher than normal radiation readings by unknown sourceRe think of nuclear option with worldwide review of Re-think of nuclear option with worldwide review of earthquakes and flooding protection and possible upgrade of seismic design standardsSome older nuclear power plants may face premature shutdown

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How to address beyond design basis accidents?

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Radiation – how bad is it?Mar 21 US Nuclear Regulatory Commission Mar 21, US Nuclear Regulatory Commission believed the situation appeared stabilising. International Atomic Energy Agency (IAEA) stated that the situation remained very seriousyHigh levels of beta-gamma contamination had been found at distances between 10-36 miles (16-58 km) from the plant; however, no significant levels of more harmful alpha radiation were detected within the 12-mile (20km) exclusion zone that remains in place around the siteIAEA said that radiation levels in major Japanese cities remained below those harmful to human health

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A 19-mile (30km) no-fly zone around the plant remains in effect

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Radiation effect

Background radiation from cosmic sources, natural and man made sources, coal fired power l tplants

Internal radiation source versus external sourceCleansing can remove most particles from fallout g pType and period of effects depends on source term and half life

– Alpha particles cause great damage but does not Alpha particles cause great damage but does not penetrate much. Less harm unless inside body

– Beta particles travel several feet in open air and are easily stopped by solid materials

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are easily stopped by solid materials– Gamma ray can penetrate skin and cause

extensive damage to organ

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Radiation effect

The body responds by trying to repair this damage, but sometimes it is too severe or widespread to make repair possible. There is also a danger of mistakes in the natural repair processdanger of mistakes in the natural repair processRegions of the body that are most vulnerable to radiation damage include the cells lining the intestine and stomach, and the blood-cell

d i ll i th b producing cells in the bone marrowThe extent of the damage caused is dependent on how long people are exposed to radiation, and at what levelPotassium iodide tablets can only address I-131 and must be take before hand to saturate thyroid gland from absorption of I-131

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Should you buy salt?

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Radiation and dose

Bq radioactivity in decays per unit time 1 becquerel = 1 disintegration per second

Gy absorbed dose of ionizing radiation1 gray = absorbed 1 joule of radiation per kg of absorbing

t i lmaterial

Sv equivalent dose of ionizing radiationSievert is a measure of the radiation dose to tissue where an attempt has been made to allow for the different relative biological effects of different types of ionizing radiation.

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g yp g

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Background radiation

Natural sources account for most of the radiation we all receive each year from a variety of natural and artificial sources

Sources in the earth; these include sources in food and water which are – Sources in the earth; these include sources in food and water, which are incorporated in the body, and in building materials and other products that incorporate those radioactive sources

– Sources from space, in the form of cosmic rays Sources from space, in the form of cosmic rays – Sources in the atmosphere, radon gas from the Earth's crust and

subsequently decays into radioactive atoms that become attached to airborne dust and particulates

– Man-made, x-ray, chemotherapy , ionisation smoke alarm, night sights, coal-fired power plants

Personal dose calculator:

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http://www.epa.gov/rpdweb00/understand/calculate.html

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Background radiation

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Ambient background gamma radiation

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R di ti t F k hi I M h 18Radiation at Fukushima I, March 18

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Play animation file

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Some comparative radiation doses and their effectsSome comparative radiation doses and their effects2 mSv/yr Typical background radiation experienced by everyone (average 1.5 mSv

in Australia, 3 mSv in North America)1 5 to 2 0 mSv/yr Average dose to Australian uranium miners above background and1.5 to 2.0 mSv/yr Average dose to Australian uranium miners, above background and

medical2.4 mSv/yr Average dose to US nuclear industry employeesUp to 5 mSv/yr Typical incremental dose for aircrew in middle latitudes9 mSv/yr Exposure by airline crew flying the New York – Tokyo polar route10 mSv/yr Maximum actual dose to Australian uranium miners.20 mSv/yr Current limit (averaged) for nuclear industry employees and uranium

miners50 mSv/yr Former routine limit for nuclear industry employees. It is also the dose rate

which arises from natural background levels in several places in Iran Indiawhich arises from natural background levels in several places in Iran, India and Europe

100 mSv/yr Lowest level at which any increase in cancer is clearly evident. Above this, the probability of cancer occurrence (rather than the severity) increases with dose

350 mSv/lifetime Criterion for relocating people after Chernobyl accident1,000 mSv cumulative Would probably cause a fatal cancer many years later in 5 of every 100

persons exposed to it (i.e. if the normal incidence of fatal cancer were 25%, this dose would increase it to 30%)

1 000 mSv single dose Causes (temporary) radiation sickness such as nausea and decreased

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1,000 mSv single dose Causes (temporary) radiation sickness such as nausea and decreased white blood cell count, but not death. Above this, severity of illness increases with dose

5,000 mSv single dose Would kill about half those receiving it within a month10,000 mSv single dose Fatal within a few weeks

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USS Reagan ran away?

U.S. aircraft carrier is exposed to radiation when it sailed through the radioactive sailed through the radioactive cloud in the Pacific OceanAs a result, in one hour, the crew who were on deck receiving the radioactive the content that is equivalent to content that is equivalent to the usual content of human received in a month

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Trajectory of air mass reaching Hong Kong 8 a.m. 16 March 2011

8 p.m. 21 March 2011

8 a.m. 17 March 2011

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Interpreting media news storiesInterpreting media news stories….What media say What they may mean

Nuclear power plant exploded! An explosion at Unit 1 damaged the outer wall of theNuclear power plant exploded! An explosion at Unit 1 damaged the outer wall of the reactor building

People rushing to get iodine and salt to prevent radioactive

i i

People mistakenly think taking salt is helpful in prevent nuclear exposure

contamination

Japan possesses knowledge in making nuclear weapon and Unit 3 is making bomb grade plutonium

Wikipedia shows everything you need to know. MOX is a mixture of surplus weapons-grade plutonium and depleted uranium to recycle nuclear wasteg g p p y

Everything fails, cover up from plant official

Equipment performed per design and failed beyond design basis. Lack of information due to failure of communication network

Japan was warned about this accident months ago

Risk Assessments were conducted that mapped out all foreseeable accidents

TEPCO did not inject seawater i di l i

There was no power, pump, pipe work and boric acid il bl d 1 d hi id h b i

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immediately to save investment available on day-1 to do this outside-the-box action

Nuclear is evil, we can phase out nuclear power by energy saving

Stop using your iphone, ipad, …

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Communication during crisis

Fact sheet or crisis information pack should be readily available be preparedFact sheet or crisis information pack should be readily available – be preparedA quick press release with concise facts can ease public panic – prompt deliveryInformation release at regular time following crisis

M i t i ti it b dil ibl t th di – Maintain connectivity , be readily accessible to the news media – Clarity of actions and words is important– Engage all stakeholders, show empathy for the people involved, – Always give the facts, strike down rumorsy g ,– Acknowledging the unknown and what is being done to address the knowledge gap– Streamline communication processes,– Maintain information security , ensure uninterrupted audit trails

Deliver more than sufficient volume communications – Deliver more than sufficient volume communications – Support multi-channel communications, e.g., twitters, – Good track record in communication

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How do you rate TEPCO in crisis communication?

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Food for thought…Fukushima is an early BWR design and just received extension after design lifeFukushima is an early BWR design and just received extension after design lifeSpent fuel is the main source of contamination at this time, unless the torus is ruptured. Must have power and cooling to prevent worsening Give out concise information and fact sheets at the onset of a crisis can reduce Give out concise information and fact sheets at the onset of a crisis can reduce rumour and help build up public confidenceMust be able to distinguish good/bad Information from certain newspaperCommon mode failure can cause loss of all redundancy functional and physicalCommon mode failure can cause loss of all redundancy, functional and physicalHow to get budget to prepare for beyond design basis accidents?Economical dependence – short term loss of parts supplies from Japan and from countries depends on Japan in providing proprietary componentscountries depends on Japan in providing proprietary componentsAre lessons learned from other misfortunate being adopted in practice, or having “it won’t happen in my shift” attitude?If nuclear is bad what do we have today to replace it while keeping your iphone

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If nuclear is bad, what do we have today to replace it while keeping your iphone on

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