Types of Burst
Exo-Atmospheric: Nuclear explosion above 30,000
metres causes disruption to the ionosphere and thus to communication
systems. (Considering most of our current communications are now
via satellites, this is an effective, indirect form of attack.)
Endo-Atmospheric: Nuclear explosion
within the atmosphere causes disruption to the communication systems
and accelerates the radiation over a greater area due to the winds
at higher altitudes.
Air-Burst: An airburst produces
a powerful blast wave and secondary wave twice as powerful as a ground
burst. Tactical nuclear weapons are most likely to be set for
low airburst to optimize the blast effects. Very little residual
radiation (fallout) is caused but rain out might occur.
Ground-Burst: A ground-burst explodes
on or near the ground forming a crater and producing radioactive
fallout.
Sub-Surface Burst: A sub-surface
device is detonated below the surface of earth or water. Strong
shock waves are formed. Intense fallout is caused if the fireball
rises above the surface.
Effects of Nuclear Explosions
Immediate Effects
- Blinding flash.
- Intense heat.
- Shock and blast pulse from the centre of explosion
followed by a negative pressure wave back towards centre of explosion
causing “Push Pull” effect, causing structural damage.
- Electro-magnetic phenomena which could short out
electrical equipment if not protected and may cause major disruption
to radar and radio transmissions.
- Initial radiation consisting of:
- Neutrons.
- Gamma rays.
- Initial radiation passing through electrical equipment
may cause Transient Effects on Electronics (TREE)
Residual Effects
Residual radiation consists of Neutron Induced Activity (NIA) and fallout.
NIA is contamination remaining in the ground around the Ground Zero
(Usually up to 1.5Km distance depending on the yield of the device.)
Dirt drawn up with the fireball will be contaminated
and when it falls to ground will form radioactive fallout. This
radiation can be spread for hundreds of miles from the Ground Zero
by upper atmospheric winds (Remember Chernobyl). Local concentrations
of radioactivity may form when rainfall has increased the fallout
level. Two types of radiation of significance are present in
the radioactive dust particles in fallout these are:
- Beta Particles. Beta particles have a
range of a few metres. They will not penetrate beyond skin
unless the individual has uncovered cuts or abrasions. However,
they will cause “Beta Burns” if left on unprotected
skin. They are dangerous if inhaled or swallowed. Earth
or light metals can stop them.
- Gamma Rays. Gamma rays are highly penetrating
and hazardous. They can be progressively reduced by dense material
such as lead, earth or concrete.
Residual radiation will be reduced by:
- Time.
- Shielding.
- Distance.
Nuclear Immediate Action Drill
If you are unable to gain cover and you are caught out in the
open when the explosion occurs you must follow the Nuclear Immediate
Action (IA) drill on sensing the flash effect. The sequence is
detailed below:
- Shut your eyes.
- Drop to ground.
- Place your hands under your body.
- Remain flat until the Heat and
both the Positive & Negative blast
wave have passed over you.
With countries such as Iran, Syria, Pakistan and
North Korea, having a nuclear, biological or chemical capability
and currently having problems internally and within the global community,
it is not beyond probability for such material to go missing or reallocated
and once again ends up in the wrong hands. The low tech variation
to a TNW is a Dirty Bomb.
Dirty Bomb
A “dirty bomb” or radiological dispersal device (RDD) is
a conventional explosive or bomb containing radioactive materials. Dirty
bombs are conventional explosives with radioactive materials designed
to disperse a hazardous and less then lethal amounts of radioactive material
over a general area. It is important to note that a dirty bomb
is NOT a nuclear bomb and does not involve a nuclear explosion. Any
type of radioactive material could be used in a dirty bomb. In general
these devices would be unlikely to cause serious health effects beyond
those caused by the initial detonation of the device.
(See diagram)
|