WASH-740
Encyclopedia
WASH-740, "Theoretical Possibilities and Consequences of Major Accidents in Large Nuclear Power Plants" (also known as "The Brookhaven Report") estimated maximum possible damage from a meltdown with no containment building
at a large nuclear reactor
. The report was published by the U.S. Atomic Energy Commission
(USAEC) in 1957.
The conclusions of this study estimated the possible effects of a "maximum credible accident" for nuclear reactor
s then envisioned as being 3400 deaths, 43,000 injuries and property damage of $7 billion. The estimate of probability was one in a hundred thousand to one in a billion per reactor-year. When WASH-740 was revised in 1964-65 to account for the larger reactors then being designed, the new figures indicated that there could be as many as 45,000 deaths, 100,000 injuries, and $17 billion in property damage.
However, the assumptions underlying the results were unrealistic (including the worst meteorological conditions, no containment building
, and that half the reactor core is released into the atmosphere as micrometre-sized pellets without any examination of how this might occur). These were due to conservatism (estimating the maximum possible damage) and the need to use atomic bomb fallout
data, which had been collected from tests (computers in 1955 being greatly insufficient to do the calculations).
As knowledge, models and computers improved the conclusions of this report were replaced by those of first WASH-1400
(1975, The Rasmussen Report), then CRAC-II
(1982), and most recently NUREG-1150
(1991). Now all of these studies are considered obsolete (see the disclaimer to NUREG-1150), and are being replaced by the State-of-the-Art Reactor Consequence Analyses
study.
Containment building
A containment building, in its most common usage, is a steel or reinforced concrete structure enclosing a nuclear reactor. It is designed, in any emergency, to contain the escape of radiation to a maximum pressure in the range of 60 to 200 psi...
at a large nuclear reactor
Nuclear reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
. The report was published by the U.S. Atomic Energy Commission
United States Atomic Energy Commission
The United States Atomic Energy Commission was an agency of the United States government established after World War II by Congress to foster and control the peace time development of atomic science and technology. President Harry S...
(USAEC) in 1957.
The conclusions of this study estimated the possible effects of a "maximum credible accident" for nuclear reactor
Nuclear reactor
A nuclear reactor is a device to initiate and control a sustained nuclear chain reaction. Most commonly they are used for generating electricity and for the propulsion of ships. Usually heat from nuclear fission is passed to a working fluid , which runs through turbines that power either ship's...
s then envisioned as being 3400 deaths, 43,000 injuries and property damage of $7 billion. The estimate of probability was one in a hundred thousand to one in a billion per reactor-year. When WASH-740 was revised in 1964-65 to account for the larger reactors then being designed, the new figures indicated that there could be as many as 45,000 deaths, 100,000 injuries, and $17 billion in property damage.
However, the assumptions underlying the results were unrealistic (including the worst meteorological conditions, no containment building
Containment building
A containment building, in its most common usage, is a steel or reinforced concrete structure enclosing a nuclear reactor. It is designed, in any emergency, to contain the escape of radiation to a maximum pressure in the range of 60 to 200 psi...
, and that half the reactor core is released into the atmosphere as micrometre-sized pellets without any examination of how this might occur). These were due to conservatism (estimating the maximum possible damage) and the need to use atomic bomb fallout
Nuclear fallout
Fallout is the residual radioactive material propelled into the upper atmosphere following a nuclear blast, so called because it "falls out" of the sky after the explosion and shock wave have passed. It commonly refers to the radioactive dust and ash created when a nuclear weapon explodes...
data, which had been collected from tests (computers in 1955 being greatly insufficient to do the calculations).
As knowledge, models and computers improved the conclusions of this report were replaced by those of first WASH-1400
WASH-1400
WASH-1400, 'The Reactor Safety Study, was a report produced in 1975 for the Nuclear Regulatory Commission by a committee of specialists under Professor Norman Rasmussen. It "generated a storm of criticism in the years following its release"...
(1975, The Rasmussen Report), then CRAC-II
CRAC-II
CRAC-II is both a computer code and the 1982 report of the simulation results performed by Sandia National Laboratories for the Nuclear Regulatory Commission...
(1982), and most recently NUREG-1150
NUREG-1150
NUREG-1150 is an improvement on WASH-1400 and CRAC-II using the results of plant-specific Probabilistic Risk Assessments...
(1991). Now all of these studies are considered obsolete (see the disclaimer to NUREG-1150), and are being replaced by the State-of-the-Art Reactor Consequence Analyses
State-of-the-Art Reactor Consequence Analyses
The State-of-the-Art Reactor Consequence Analyses is a study of nuclear power plant safety conducted by the Nuclear Regulatory Commission...
study.
External links
- Serious Accidents (in Nuclear Power Plants)
- Nuclear Power Pro/Con
- History of WASH-740
- Reactor Safety: 1953-1978
- The WASH-740 report
See also
- Nuclear safety in the U.S.
- Nuclear powerNuclear powerNuclear power is the use of sustained nuclear fission to generate heat and electricity. Nuclear power plants provide about 6% of the world's energy and 13–14% of the world's electricity, with the U.S., France, and Japan together accounting for about 50% of nuclear generated electricity...
- Nuclear power plantNuclear power plantA nuclear power plant is a thermal power station in which the heat source is one or more nuclear reactors. As in a conventional thermal power station the heat is used to generate steam which drives a steam turbine connected to a generator which produces electricity.Nuclear power plants are usually...
- Nuclear accidents in the United StatesNuclear accidents in the United StatesAccording to a 2010 survey of energy accidents, there have been at least 56 accidents near nuclear reactors in the United States . The most serious of these was the Three Mile Island accident in 1979...