Improvised Explosive Devices (IEDs)

Akshad VeerM.Sc.II

(Forensic Physics and Ballistics)

Roll No.05

IntroductionIED crude improvised explosive devices crude improvised explosive devices nature is depends upon the ingenuity of the culprit

and on the availability of materials

Factors affecting Improvised Explosive Devices (IEDs) constructions

Knowledge of the

builder Ingenuity of the builder

Skill of the builder

Access to nonexplosiv

e component

Access to explosive

Appearance of an Improvised Explosive Devices (IEDs)

Combination of open and close: partially hidden from viewClose: whose component are hidden from view by the

use of an external container. Example backpack, suicide- bombing type device latter bomb.

Open: whose component can be completely.

Containers Strings, paper, cloth, bottles, bulbs,

tins, torch covers, bamboo poles, coconut shells, earthen pots and pipes.

small size, weight less than a kilogram. The terrorists have promoted new names for IEDs:

Internal: pressure Eternal: transportation

Explosives1. Military or commercial explosives.2. Small -arms propellants.3. Nitrate mixtures. Nitrates of ammonia, barium, potassium have been used

combination4. Chlorate or permanganate mixtures. same way as nitrate mixtures, more disastrous results. used as initiators for fires and other explosives. For example, a mixture of potassium chlorate and

sugar catches fire immediately on coming into contact with sulphuric acid.

5) highly inflammable organic liquids have excellent explosive properties. The famous (or infamous) Molotov cocktails

contain only petrol. explosion, in 2001, of the World Trade Towers, New York

Initiation Devices They determine the nature and the nomenclature of the

bomb. Initiation devices utilize one of the following sources of energy.

Mechanical: fall, crushing, impact, friction. Shock: induced by other explosions. Heat: flame, steam, exhaust pipe emissions. Spark: flame, cinders. Chemicals: for example, sugar-chlorate-sulphuric acid

mixture. Miscellaneous: light, infra red rays, laser, ultrasound

waves. Electric current.

Throw-down: Explodes due to

initiation by the impact on a sensitive material kept inside.

Suitable chlorate mixture, fulminates mixtures, other chemical mixtures

smallest effective bomb

Fuse Bombs : fitted with a safety fuse. ignited before using the

bomb. Fuse cord of convenient

length is used so that it does not explode while being thrown.

Lighted fuse puts the explosive charge on fire and the device explodes.

This is the easiest and safest arrangement for initiation.

Percussion Cap Bomb

Time bomb-(Clocks or watches ) One end of the wire of the circuit is

connected to the metallic needle of the watch (usually the hour hand) and the other end at the hour digit (or site).

When the hour-hand touches the digit or the site the electric circuit is completed.

And activates the initiator which explodes the explosive.

Suitcase bombs were usually time bomb

Letter bomb Explosive chosen is so sensitive that it

explodes on rough handling. A friction sensitive explosive is placed at

possible tearing sites. tearing process explodes the letter bomb. miniature percussion cap (or detonator)

and spring operated hammer is placed in the postal parcel.

on opening the packet, strikes the cap and explodes the explosive.

References

James T. Thurman ,Practical Bomb Scene Investigation, Second Edition

B. R. Sharma, Firearm in Criminal Investigation and Trials