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Al Mac Acronym Guide v 1.0 March 20

The information, we have been sharing, is chock full of acronyms and technical terminology.

Unless you are already familiar with a lot of it, the specialized terminology can get in the way of clarity of understanding.  So here's my translation so far.  New and improved edition to be reposted some time in the future.

American Syndrome[1] = US News Media paints any event as the worst possible in history.  Thus we never know which story really is the worst, and which is the usual spin.

BWR = Boiling Water Reactors

CET = Central European Time,[2] including Vienna, where International Atomic Energy Agency (IAEA) is located.  It is GMT+1 where GMT is Greenwich Mean Time in Britain.  Due to Daylight savings time, in winter it is UTC+1, in summer it is UTC+2.  See UTC.

Chernobyl = worst nuclear accident in history.  Many news stories are referencing this in their discussions of Japan situation. Council on Foreign Relations writes[3] March 16 on long range consequences of Chernobyl cover-up.

CV = Containment Vessel (see PCV)

DLR = German Aerospace Center.  Here are links to at least a score of downloadable maps of various aspects of the Japan disaster

[1] Named after China Syndrome movie.

[3] OCHA Relief Web


EQJ = Earthquake Japan = something I am using to help organize my research notes

FAQ = Frequently Asked Questions.

FESL = Fire Extinguishing System Line

Fukushima I Daiichi[1]

Fukushima Dai-Ichi I on a map from Pacific Disaster Center (PDC), summary[2] link to detail[3] PDF.  This nuclear power plant is one of three in trouble right after March 11 earthquake and tsunami.  There’s another in trouble much farther south thanks to one of the aftershocks and accompanying tsunami.  This map has 2 circles around.  Orange middle is 3 km. Yellow outer is 10 km.  These are the initial evacuation and stay indoors zones which later got expanded

[3]$File/map.pdf?OpenElement from OCHA Relief Web


Fukushima II Daini[1]


GET = Global Expert Team

GFDRR = Global Facility for Disaster Reduction and Recovery (GFDRR)

GoJ = Government of Japan



IAEA = International Atomic Energy Agency.  The IAEA estimates that around 20 percent of nuclear reactors around the world are currently operating in areas of significant seismic activity.

IEC = IAEA’s Incident and Emergency Center

INES = International Nuclear and Radiological Event Scale runs from 0 (deviation) to 7 (major accident).[1]

  • 7 Major event
  • 6 Serious accident

·        5 Accident with wider consequences (Fukushima Dai-ichi units 1 2 3)

  • 4 Accident with local consequences (Fukushima Daiichi Unit 1 initial value)[2]
  • 3 Serious incident (Fukushima Dai-ichi unit 4, Fukushima Dai-ni units 1 2 4 unfinished)[3]
  • 2 incident
  • 1 anomaly
  • 0 below scale

INES events are rated in reference to three attributes:

  • People & Environment,
  • Radiological Barriers & Control, and
  • Defense in Depth.

[2] Expected to go up.

[3] Incidents are continuing, so INES rating may change.


ISSC = IAEA’s International Seismological Safety Centre

JACT = Something I added to make some of the content, particularly the Time Line, more readable for me.  It means to me that some Japan actions are implemented due to their legal check list of what to do when situation reaches some stage of severity.  Later I hope to learn more about these various stages.

  • JACT-10 = Article 10 of the Act on Special Measures Concerning Nuclear Emergency Preparedness
  • JACT-15 = Article 15 of the Act on Special Measures Concerning Nuclear Emergency Preparedness
  • JACT-15-3 = Article 15, Paragraph-3, of the Act on Special Measures Concerning Nuclear Emergency Preparedness
  • JACT-64-3 = Article 64, Paragraph-3, of the Act on Special Measures Concerning Nuclear Emergency Preparedness

JAEA = Japan Atomic Energy Agency

JST = Japan Standard (local) Time is UTC+9.  See UTC.

KM = Kilometer.  10 Km = 6 miles (approx)

MUWC  = Make up Water Condensate System

NER = Nuclear Event Reports[1]

NEWS = Nuclear Event Web Based System[2] jointly managed by The International Atomic Energy Agency, the OECD Nuclear Energy Agency and the World Association of Nuclear Operators.

NISA = Japan’s Nuclear and Industrial Safety Agency

NPS = Nuclear Power Station

NRC = US Nuclear Regulatory Commission

News releases are available through a free listserv subscription at the following Web address: The NRC homepage at also offers a SUBSCRIBE link. E-mail notifications are sent to subscribers when news releases are posted to NRC's website.



Office of Public Affairs Telephone: 301/415-8200

Washington, D.C. 20555-0001

E-mail: ***@***.*** Site:


It has sent experts to help Japan.[3]

OCHA = United Nations Office for the coordination of humanitarian affairs

OSOCC = UN Onsite Operations and Coordination Centre

P + definitions (1 Mar 21)

PBMR = Pebble Bed Modular Reactor.  One is under construction in South Africa.

For a brief description of the PBMR design, see

See: -- for a short video demonstrating this old technology.

PCV = Primary Containment Vessel[4]

[4] See Credible Science explanations of the various containment levels (in my nuclear notes).


Q+A = Questions and Answers

QRT = Quick Reaction Team


RANET = IAEA’s Response and Assistance Network. The network consists of nations which can offer specialized assistance after a radiation incident or emergency.

REMPAN = WHO’s Radiation Emergency Medical Preparedness and Assistance Network

RHR = Residual Heat Removal System

RPV = Reactor Pressure Vessel

Sources, Primary = the horse's mouth, where often the news media is the other end of the horse.

Sources, Secondary = people who we hope are quoting primary sources, but may be influenced by what communicated by other end of the horse.

Spent fuel removed from a nuclear reactor is highly radioactive and generates intense heat. Nuclear plant operators typically store this material in pools of water which cool the fuel and shield the radioactivity. Water in a spent fuel pool is continuously cooled to remove heat produced by spent fuel assemblies. According to IAEA experts, a typical spent fuel pool temperature is kept below 25 °C under normal operating conditions. The temperature of a spent fuel pool is maintained by constant cooling, which requires a constant power source.

Given the intense heat and radiation which spent fuel assemblies can generate, spent fuel pools must be constantly checked for water level and temperature. If fuel is no longer covered by water or temperatures reach a boiling point, fuel can become exposed and create a risk of radioactive release. The concern about the spent fuel pools at Fukushima Dai-ichi is that sources of power to cool the pools have been compromised.

Tepco = Tokyo Electric Power Company – it runs the Fukushima nuclear plants which have been in the news a lot

TMI = Three Mile Island

Tokai =?= Tohoku Electric Power Co., Inc – I think it runs the Onagawa nuclear plant

UNSCEAR = United Nations Scientific Committee on the Effects of Atomic Radiation (UNSCEAR)

USAID = United States Agency for International Development

UTC = Coordinated Universal Time.[1] Figuring this out is important due to news about Japan coming out from different agencies in terms of their time zones around the world.  See CET, JST.  Examples:

  • Britain (GMT) = UTC.
  • CET (Central Europe) is UTC+1 in winter (daylight savings), UTC+2 in summer.
  • American East Coast is UTC+5.
  • JST (Japan) is UTC+9.

WHO = World Health Organization

WMO = World Meteorological Organization

WNN = World Nuclear News[2]

Groups this Group Post belongs to: 


Meltdown is a term thrown around a lot in the media, sometimes they say partial meltdown, so let’s try to include a science definition for the layman.[1]

The fuel, for a nuclear power plant, generates heat, which needs to be cooled when the plant is shut down.  Also the spent fuel goes in “ponds.”[2]  If not properly cooled, high temperatures release a variety of unwanted chemicals and other effects.  If, due to high temperatures, the fuel becomes sufficiently liquid, it can pour downwards. 

That happened at Three Mile Island.

Depending on the design of the containment, there is then what happens to the concrete and steel bottom when this extremely hot fuel gets there.

Thus it is important to know at what temperatures the unwanted effects occur, and what temperatures were reached in the Japanese reactors.  From what I have heard, we are not there yet.

[2] For USA see Yucca Mountain, around which there is some controversy.



Alister Wm Macintyre

One of these pools allegedly ran out of cooling water, and caused one of the Japanese problems, so let’s try to include a science definition for the layman.[1]

After nuclear fuel has exhausted what nuclear energy we can get from it in the reactor, it moves to water pools and large casks which use air to cool the fuel rods.  The pools are often located near the reactor, in containment arrangements similar to the reactor, both because of the cooling needed, plus to shield the radiation coming from there.  This spent nuclear fuel (SNF) has heat, but not as intense as the heat from a reactor recently shut down, like those threatened by earthquake and tsunami.

Normally the SNF can be stored in the pools indefinitely, so long as the cooling system is working.  Unfortunately the cooling system got broke by the earthquake and tsunami, and some of the later incidents.

Alister Wm Macintyre

howdy folks