Delivered at FCDTS Karachi in NBC Course by Saad Abdul Wahab

1. Presentation on Nuclear
Weapons
Saad Abdul Wahab
M.Sc Applied Chemistry & Chemical Technology (Specialization in Petroleum Technology From University of Karachi)
BE Textile, from Synthetic Fiber Development & Application Center.
IOSH Managing Safely.
Certifications of HSE, EMS-14001, OSHAS-18001, QMS 9001:2008, FSMS-22000:2005, SSCL (17025) by SGS & NILAT.
IRCA approved Lead Auditor OHSAS 18001:2004 .
HSE Rules & Laws in Industries from SDC.
Authorized Safety Instructor from DG Federal Civil Defence Pakistan.

2. Topics:
• Effects of blast
• Area of destruction
• Fringe Area
• Fall out
• Radiation Sequence
• Nuclear fission & fusion
• Chain Reaction
• Radiation
• Thermal Burns
• Q/A

3. Nuclear Physics
• Nuclear physics is the field of physics that studies the constituents and
interactions of atomic nuclei. The most commonly known applications of
nuclear physics are nuclear power generation and nuclear
weapons technology, but the research has provided application in many
fields, including those in nuclear medicine and magnetic resonance
imaging, ion implantation in materials engineering, and radiocarbon
dating in geology and archaeology.
• The field of particle physics evolved out of nuclear physics and is typically
taught in close association with nuclear physics.

4. Effects of Nuclear Explosion
• 1 Direct effects
– 1 Blast damage
– 2 Thermal radiation
• 2 Indirect effects
– 1 Electromagnetic pulse
– 2 Ionizing radiation
– 3 Earthquake
– 4 Summary of the effects
• Little boy (Bomb)
• Angola-gay (Bomber)

6. Understand the hazards of Nuclear Attacks
• Effects:
• The energy released from a nuclear weapon detonated in
the troposphere can be divided into four basic categories:
• Blast—40–50% of total energy
• Thermal radiation—30–50% of total energy
• Ionizing radiation—5% of total energy (more in a neutron bomb)
• Residual radiation—5–10% of total energy

7. Area of heavy destruction
• Direct Effect:
• Much of the destruction caused by a nuclear explosion is due to blast effects. Most
buildings, except reinforced or blast-resistant structures, will suffer moderate
damage when subjected to overpressures of only 35.5 kilopascals (kPa)
(5.15 pounds-force per square inch or 0.35 atm).

8. Effects
Explosive yield / Height of Burst
1 kt / 200 m 20 kt / 540 m 1 Mt / 2.0 km 20 Mt / 5.4 km
Blast—effective ground range GR / km
Urban areas completely levelled
(20 psi or 140 kPa)
0.2 0.6 2.4 6.4
Destruction of most civilian
buildings (5 psi or 34 kPa)
0.6 1.7 6.2 17
Moderate damage to civilian
buildings (1 psi or 6.9 kPa)
1.7 4.7 17 47
Railway cars thrown from tracks
and crushed (62 kPa; values for
other than 20 kt are extrapolated
using the cube-root scaling)
≈0.4 1.0 ≈4 ≈10
Thermal radiation—effective ground range GR / km
Conflagration 0.5 2.0 10 30
Third degree burns 0.6 2.5 12 38
Second degree burns 0.8 3.2 15 44
First degree burns 1.1 4.2 19 53
Effects of instant nuclear radiation—effective slant range1 SR / km
Lethal2 total dose (neutrons and
gamma rays)
0.8 1.4 2.3 4.7
Total dose for acute radiation
syndrome2 1.2 1.8 2.9 5.4

9. Nuclear Warfare
• Nuclear warfare (sometimes atomic
warfare or thermonuclear warfare), is a military conflict or
political strategy in which nuclear weaponry is used to inflict
damage on an opponent. Compared to conventional
warfare, nuclear warfare can be vastly more destructive in
range and extent of damage, and in a much shorter time
frame. A major nuclear exchange could have severe long-
term effects, primarily from radiation release, but also from
the production of high levels of atmospheric pollution
leading to a "nuclear winter" that could last for decades,
centuries, or even millennia after the initial attack.[1][2] A
large nuclear war is considered to bear existential risk for
civilization on Earth.[3][4] Importantly however, despite
modern civilization being at risk, assuming weapons
stockpiles at the previous cold war heights, analysts
and physicists have found that billions of humans would
nevertheless survive a global thermonuclear war.[5][6][7][8]
• Only two nuclear weapons have been used in the course of
warfare, both by the United States near the end of World
War II. On August 6, 1945, auranium gun-type device (code
name "Little Boy") was detonated over the Japanese city
of Hiroshima. Three days later, on August 9,
a plutoniumimplosion-type device (code name "Fat Man")
was detonated over Nagasaki, Japan. These
two bombings resulted in the deaths of approximately
200,000 Japanese people (mostly civilians) from acute
injuries sustained in the detonations.
Mushroom cloud from the atomic explosion over
Nagasaki rising 60,000 feet into the air on the
morning of August 9, 1945.

10. Fringe Area
• Fringe science is scientific inquiry in an established field of study that
departs significantly from mainstream or orthodox theories, and is classified
in the "fringes" of a credible mainstream academic discipline.
• Three classifications of scientific ideas have been identified (center, frontier,
fringe) with mainstream scientists typically regarding fringe concepts as
highly speculative or even strongly refuted. However, according to
Rosenthal "Accepted science may merge into frontier science, which in turn
may merge into more far-out ideas, or fringe science. Really wild ideas may
be considered beyond the fringe, or pseudoscientific."

11. Nuclear fallout
• Nuclear fallout, or simply fallout, also known as Black Rain, is the residual
radioactive material propelled into the upper atmosphere following a nuclear
blastor a nuclear reaction conducted in an unshielded facility, 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, but such dust can also originate from a damaged nuclear plant.
• This radioactive dust, consisting of material either directly vaporized by a nuclear
blast or charged by exposure, is a highly dangerous kind of radioactive
contamination.

12. Radiation Sickness
• Acute radiation syndrome (ARS), also known as radiation poisoning, radiation
sickness or radiation toxicity, is a constellation of health effects which present
within 24 hours of exposure to high amounts of ionizing radiation. The radiation
causes cellular degradation due to destruction of cell walls and other key
molecular structures within the body; this destruction in turn causes the
symptoms. The symptoms can begin within one or two hours and may last for
several months. The terms refer to acute medical problems rather than ones that
develop after a prolonged period.
• Similar symptoms may appear months to years after exposure as chronic radiation
syndrome when the dose rate is too low to cause the acute form. Radiation
exposure can also increase the probability of developing some other
diseases, mainly different types of cancers. These diseases are sometimes referred
to as radiation sickness, but they are never included in the term acute radiation
syndrome.

13. Phase Symptom
Whole-body absorbed dose (Gy)
1–2 Gy 2–6 Gy 6–8 Gy 8–30 Gy
Greater Than
30 Gy
Immediate
Nausea and vo
miting
5–50% 50–100% 75–100% 90–100% 100%
Time of onset 2–6 h 1–2 h 10–60 min < 10 min Minutes
Duration < 24 h 24–48 h < 48 h < 48 h
N/A (patients die in
< 48 h)
Diarrhea None None to mild (< 10%) Heavy (> 10%) Heavy (> 95%) Heavy (100%)
Time of onset — 3–8 h 1–3 h < 1 h < 1 h
Headache Slight Mild to moderate (50%) Moderate (80%) Severe (80–90%) Severe (100%)
Time of onset — 4–24 h 3–4 h 1–2 h < 1 h
Fever None
Moderate increase (10-
100%)
Moderate to severe
(100%)
Severe (100%) Severe (100%)
Time of onset — 1–3 h < 1 h < 1 h < 1 h
CNS function
No
impairment
Cognitive impairment
6–20 h
Cognitive impairment >
24 h
Rapid
incapacitation
Seizures, Tremor,
Ataxia, Lethargy
Latent period 28–31 days 7–28 days < 7 days none none
Illness
Mild to
moderate Le
ukopenia
Fatigue
Weakness
Moderate to severe
Leukopenia
Purpura
Hemorrhage
Infections
Epilation after 3 Gy
Severe leukopenia
High fever
Diarrhea
Vomiting
Dizziness and
disorientation
Hypotension
Electrolyte disturbance
Nausea
Vomiting
Severe diarrhea
High fever
Electrolyte
disturbance
Shock
N/A (patients die in
< 48h)
Mortality
Without care 0–5% 5–100% 95–100% 100% 100%
With care 0–5% 5–50% 50–100% 100% 100%
Death 6–8 weeks 4–6 weeks 2–4 weeks 2 days–2 weeks 1–2 days

14. Nuclear fission
• Nuclear fission is the reverse process of fusion. For nuclei heavier than nickel-62 the binding
energy per nucleon decreases with the mass number. It is therefore possible for energy to be
released if a heavy nucleus breaks apart into two lighter ones.
• The process of alpha decay is in essence a special type of spontaneous nuclear fission. This
process produces a highly asymmetrical fission because the four particles which make up the
alpha particle are especially tightly bound to each other, making production of this nucleus in
fission particularly likely.
• For certain of the heaviest nuclei which produce neutrons on fission, and which also easily absorb
neutrons to initiate fission, a self-igniting type of neutron-initiated fission can be obtained, in a so-
called chain reaction. Chain reactions were known in chemistry before physics, and in fact many
familiar processes like fires and chemical explosions are chemical chain reactions. The fission
or "nuclear" chain-reaction, using fission-produced neutrons, is the source of energy for nuclear
power plants and fission type nuclear bombs, such as those detonated by the United
States inHiroshima and Nagasaki, Japan, at the end of World War II. Heavy nuclei such
as uranium and thorium may also undergo spontaneous fission, but they are much more likely to
undergo decay by alpha decay.
• For a neutron-initiated chain-reaction to occur, there must be a critical mass of the element
present in a certain space under certain conditions. The conditions for the smallest critical mass
require the conservation of the emitted neutrons and also their slowing or moderation so there is a
greater cross-section or probabability of them initiating another fission. In two regions
of Oklo, Gabon, Africa, natural nuclear fission reactors were active over 1.5 billion years
ago. Measurements of natural neutrino emission have demonstrated that around half of the heat
emanating from the Earth's core results from radioactive decay. However, it is not known if any of
this results from fission chain-reactions.

16. Nuclear Fusion
• In nuclear fusion, two low mass nuclei come into very close contact with
each other, so that the strong force fuses them. It requires a large amount
of energy to overcome the repulsion between the nuclei for the strong
or nuclear forces to produce this effect, therefore nuclear fusion can only
take place at very high temperatures or high pressures. Once the process
succeeds, a very large amount of energy is released and the combined
nucleus assumes a lower energy level. The binding energy per nucleon
increases with mass number up until nickel-62. Stars like the Sun are
powered by the fusion of four protons into a helium nucleus,
two positrons, and two neutrinos. The uncontrolled fusion of hydrogen
into helium is known as thermonuclear runaway. A frontier in current
research at various institutions, for example the Joint European Torus (JET)
and ITER, is the development of an economically viable method of using
energy from a controlled fusion reaction. Natural nuclear fusion is the
origin of the light and energy produced by the core of all stars including
our own sun.

18. Chain Reaction

22. Fusion Chain Reaction

23. Radiation

24. Nuclear radiations
• Types of radiation
• Nuclear radiation arises from hundreds of different kinds of unstable atoms. While many exist in nature, the
majority are created in nuclear reactions, Ionizing radiation which can damage living tissue is emitted as the
unstable atoms (radionuclides) change ('decay') spontaneously to become different kinds of atoms.
• The principal kinds of ionizing radiation are:
• Alpha particles
• These are helium nuclei consisting of two protons and two neutrons and are emitted from naturally-occurring
heavy elements such as uranium and radium, as well as from some man-made transuranic elements. They
are intensely ionizing but cannot penetrate the skin, so are dangerous only if emitted inside the body.
• Beta particles
• These are fast-moving electrons emitted by many radioactive elements. They are more penetrating than alpha
particles, but easily shielded – they can be stopped by a few millimetres of wood or aluminium. They can
penetrate a little way into human flesh but are generally less dangerous to people than gamma radiation.
Exposure produces an effect like sunburn, but which is slower to heal. Beta-radioactive substances are also
safe if kept in appropriate sealed containers.
• Gamma rays
• These are high-energy beams much the same as X-rays. They are emitted in many radioactive decays and
are very penetrating, so require more substantial shielding. Gamma rays are the main hazard to people
dealing with sealed radioactive materials used, for example, in industrial gauges and radiotherapy machines.
Radiation dose badges are worn by workers in exposed situations to detect them and hence monitor
exposure. All of us receive about 0.5-1 mSv per year of gamma radiation from cosmic rays and from
rocks, and in some places, much more. Gamma activity in a substance (e.g. rock) can be measured with a
scintillometer or Geiger counter.
• X-rays are also ionizing radiation, virtually identical to gamma rays, but not nuclear in origin.
• Cosmic radiation consists of very energetic particles, mostly protons, which bombard the Earth from outer

25. Thermal Burns
• A burn is a type of injury to flesh or skin caused
by heat, electricity, chemicals, friction, or radiation. Burns that affect only the
superficial skin are known as superficial or first-degree burns. When
damage penetrates into some of the underlying layers, it is a partial-
thickness or second-degree burn. In a full-thickness or third-degree
burn, the injury extends to all layers of the skin. A fourth-degree burn
additionally involves injury to deeper tissues, such as muscle or bone.

26. Effects
Explosive yield / Height of Burst
1 kt / 200 m 20 kt / 540 m 1 Mt / 2.0 km 20 Mt / 5.4 km
Blast—effective ground range GR / km
Urban areas completely levelled (20 psi or
140 kPa)
0.2 0.6 2.4 6.4
Destruction of most civilian buildings (5 psi
or 34 kPa)
0.6 1.7 6.2 17
Moderate damage to civilian buildings (1 psi
or 6.9 kPa)
1.7 4.7 17 47
Railway cars thrown from tracks and
crushed (62 kPa; values for other than 20 kt
are extrapolated using the cube-root scaling)
≈0.4 1.0 ≈4 ≈10
Thermal radiation—effective ground range GR / km
Conflagration 0.5 2.0 10 30
Third degree burns 0.6 2.5 12 38
Second degree burns 0.8 3.2 15 44
First degree burns 1.1 4.2 19 53
Effects of instant nuclear radiation—effective slant range1 SR / km
Lethal2 total dose (neutrons and gamma
rays)
0.8 1.4 2.3 4.7
Total dose for acute radiation syndrome2 1.2 1.8 2.9 5.4

27. Prevention (Next Presentation)
– 1 Distance
– 2 Time
– 3 Shielding
– 4 Reduction of incorporation into the human body
– 5 Fractionation of dose

28. Thank You
• Q/A..??
Email: saadawkhan@yahoo.com
Cell: 0333-3235554, 0313-2338340
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