Chia Poh Ling*, Lim Chin Chin, Michael Tay Ming Kiong
2nd AFSN meeting, Brunei Darussalam, 1-3 Jun 2010 (poster presentation)
Objective: To present case studies of incidents in Singapore where common chemicals were used to make improvised explosives devices (IEDs). The ingredients used, effects of the explosions and reconstruction of the IEDs would be discussed.
Case 1: White smoke was seen emitting out of an abandoned shopping bag at the rear seat of a shopping bag. Remnants of a badly deformed and burnt bottle with a green plastic screw cap and 660 g of dark powdery material were recovered from the scene. The base of the bottle contained a colourless, acidic liquid which was found to be concentrated (37%) formalin. The powder was found to contain potassium permanganate and its products of reaction. Potassium permanganate and formalin react exothermically to produce formaldehyde, an irritant and lachrymatory gas.
Case 2: A 500 ml plastic bottle containing coloured sand-like material exploded in the victim’s hand when he threw it out of the house. A partially burnt, distorted bottle, a bottle cap, some yellow powder and the victim’s clothing were recovered at the scene. The damages in the bottle suggested that it had undergone burning and exploded. The moist brownish black material inside the bottle was found to contain aluminium, glycerol and the reaction products of potassium permanganate. The yellow powder was found to be sulphur. Potassium permanganate reacts violently with glycerin when mixed and produces a dazzling flash with smoke and high temperatures.
Cases involving the use of sparkler materials
Numerous cases involving the use of sparkler and/or sparkler materials were encountered in Singapore. The different modes in which these materials were used to construct IEDs and the effects of the explosions related to these incidents will be discussed.