Researchers hope to sniff out homemade bomb factories

Terrorists attempting to make homemade explosives could be sniffed out by law enforcement officials with a new mobile detection system being developed through an EU-funded research programme.

Researchers involved with the €4.3m LOTUS (Localisation of threat substances in urban society) project claim such detection technology could have prevented catastrophes such as London’s 7/7 bombings five years ago.

The pan-European team, which is coordinated by the Swedish Defence Research Agency (FOI), envision the possibility of installing explosive detection systems atop police vehicles that would effectively monitor urban areas for possible bomb-making activities while on normal patrol.

The system’s sensors would be able to detect whether elevated levels of suspicious  substances are in the area and then use integrated GPS technology to record the time and location the molecules are being emitted from. This information would then be sent through a wireless network to a server administered by the police.

Dr Henric Östmark, head of steering committee for the LOTUS project, said the sensors they are initially testing will be sensitive to hydrogen peroxide, which was the main chemical used in the 7/7 bombs.

In their Swedish laboratories, he said, the team have set up a replica of the home kitchen in Leeds where the lethal explosives were manufactured. Östmark said they will initially be testing three types of sensors. The first being an ‘ion mobility spectrometer’ sensor, a technology commonly used in airports for explosive screening.

The other sensors will be based on ‘differential mobility analysis’ and infrared detection. It’s early days though, Östmark points out, so the types of sensors used in the final prototype may be something entirely different. The main criteria, he said, is they are sensitive and fast.

Traditionally Östmark said explosive detection has been focused on spotting bombs after they have been produced and brought to a location for detonation. While this can work successfully at airport checkpoints, he said it is impractical in applications like underground stations because the number of passengers would be too overwhelming to scan.

Even if explosive scanning checkpoints were installed in underground stations, Östmark said, the measure would give law enforcement no time to react. ‘The person is in the station and he or she could detonate the bomb anyhow,’ he said. ‘We want to find the bombs in the production stage because it will give law enforcement more time to act.’

The process of detecting a bomb in its early production stages may seem easily prone to false alarms. For instance, there could be a number of innocuous reasons a higher concentration of hydrogen peroxide is found in the air. Östmark said their system’s central server, however, would take this into consideration and only ring alarm bells if high concentrations of suspect chemicals were found in an area over an extended period of time.

‘It takes some time to make a bomb,’ he said. ‘We calculated that if you are going to make a bomb in a kitchen, it will take at least one month to do it.’

One of the most important aspects of the LOTUS initiative will be to make sure the technology is adaptable. Östmark said any terrorist knowing that hydrogen peroxide is detectable outside the home, after all, will likely come up with a new chemical to base their bomb on.

‘We are looking at other potentials for making homemade explosives with homemade chemicals,’ he said. ‘We also ensure our sensors can be updated if the terrorist find some other way to make a bomb.’

Following laboratory tests, the LOTUS team will be testing their detection system in a real world environment driving around the neighbourhoods of Stockholm. It will then be deployed for further testing in a yet to be revealed European city.

The project, which began in 2009, is expected to produce final results by the end of 2011.