Arms Locker banner

1 - 4 of 4 Posts

9,586 Posts
Discussion Starter #1
The Phantom Threat
Detecting Chemical, Biological Agents Before It's Too Late

by Ted McKenna
Sep. 17, 2004

Soldiers can see in the darkness using thermal imagers, and they see what's happening at places thousands of miles away thanks to satellites. But how can they see an enemy that could be all around them yet weigh virtually nothing, waft through the air like pollen, and be invisible? Anthrax, Sarin, and other biological or chemical threats can pass by the scariest looking tank or missile launcher on Earth without a second glance, and they can't be stopped by any gun or knife a soldier carries.

Fear of a chemical or biological attack can affect a military force's effectiveness, even if an alarm turns out to be false. Protective suits are cumbersome and reduce the wearer's effectiveness, and units could be maneuvered off positions of significant battlefield value. Shown here is a US Marine training exercise in Al Hamra, United Arab Emirates.

The insidious nature of unconventional weapons means that even the threat of their use by an enemy can be enough to hamper military operations. Protective suits are cumbersome and reduce the wearer's effectiveness. Units could be maneuvered off positions of significant battlefield value. Thus, unconventional weapons can have an impact even if they are not actually used. For this reason, technologies that provide the earliest possible warnings of such attacks can help commanders make decisions that protect forces without degrading their capabilities unnecessarily.

As a director at the US Army's center for biological and chemical detection noted, an ounce of detection is worth a pound of antidote. But detection technology today provides only a crude gauge of an approaching threat. Geiger counters and more sophisticated devices for measuring radiation levels have long been available, but electronic devices for detecting chemical and biological agents have been available in the field only within the last couple of decades. Their ability to detect and identify still leaves a lot to be desired, say experts, although improvements are continually being made.

A member of Canada's Joint Nuclear Biological and Chemical Defence Company uses a detector to check another member for contamination during a training exercise. Militaries typically form specialized units to deal with biological, chemical, and radiological threats.

The science the devices use varies depending on the device and what type of threat it aims to detect. Back in World War I, the only detectors troops had were their noses. German mustard gas smelled like mustard, and Allied mustard gas smelled like garlic, notes historian Jeffrey K. Smart in "History of Chemical and Biological Warfare: An American Perspective," from the Textbook of Military Medicine: Medical Aspects of Chemical and Biological Warfare. Scouts provided advanced word of gas clouds, while troops already wearing their protective masks simply did "sniff" tests by pulling their masks away and taking a whiff – not an accurate means of gauging levels of agents in the air, nor healthy for the soldiers, and as the hours passed on the battlefield, their ability to smell the gas diminished anyway.

Chemical and biological warfare goes back much farther than that, of course. Warriors hundreds, even thousands of years ago dipped their arrows in poisons, and Roman soldiers were known to tip dead animals into wells to contaminate the water supplies of enemies. European settlers competing for land and resources with the native tribes of North America tribes sometimes gave the locals blankets infected with smallpox, which could quickly kill off a large percentage of populations that had no prior exposure to the virus.

The use of chemical weapons during World War I, including mustard and chlorine gas, killed some 90,000 people and led to the signing by many countries in 1928 of a protocol prohibiting their use. This picture of the Western Front was taken from behind German lines.

But modern science made possible the manufacture of large quantities of chemical and biological agents. The use of chemical weapons during WWI, including mustard gas and chlorine, killed some 90,000 people and led to the signing by many countries in 1928 of the Geneva Protocol for the Prohibition of the Use in War of Asphyxiating, Poisonous or Other Gases, and of Bacteriological Methods of Warfare. Then in 1972 came a similar Geneva protocol against the use of biological and toxin weapons.

Initial Attempts

Though Western nations essentially promised not to use biological or chemical weapons on the battlefield (although reserving the right to do so if the agents were used on them), they obviously saw the threat their own troops faced. Work went on for decades to develop detectors that could reliably identify a chemical agent, and various prototypes were created, but the first wide-scale fielding of a system was during the Persian Gulf War in 1990-1991 with the M8A1 Alarm. Contaminants in the air passed over a radioactive source in the alarm and broke up into charged pieces called ions, and when the current within the alarm indicated a critical concentration of the agent, an alarm would sound.

These 500-lb. bombs, photographed in Iraq prior to the war launched by the US and others there last year, were filled with an unspecified chemical agent. Many countries have sworn off the use of chemical and biological weapons on the battlefield but fear their continued production by certain rogue nations or non-state actors like Al Qaeda.

But diesel exhaust from vehicles and the smoke from oil wells that Saddam Hussein's troops set on fire during the conflict repeatedly set off the alarms, which then had to be verified through the use of a more sensitive detector, the M256, which wasn't an automated device at all but basically a chemistry kit for testing air samples. With false alarms as often as 20-30 minutes – as was reportedly the experience with one battalion, which simply decided to turn its detectors off – confidence in the detectors faded quickly, and false alarms continue to be a problem with detection systems.

Today, detection systems that have been widely fielded include the US military's Automated Chemical Detector Alarm (ACADA), 1,600 units of which Smiths Detection (Watford, UK) this spring received a $15-million contract to provide for the US Department of Defense, nearly all of them to the National Guard. More than 6,000 ACADAs were used in Iraq in 2003, according to the company. Newer devices like the ACADA also use ionization as the means of identification, but have become much smaller and more reliable, although undoubtedly the problem of "false positives," in which something other than a harmful agent set off the alarm, continues.

Though Smiths Detection claims in press releases that false alarms are virtually nil with its ACADA system, at least compared with the detectors used during the first Gulf War, all chemical detectors sound false alarms over things other than the threats the devices were meant to detect, said Mark Allen Miller, an expert in protecting against attacks with weapons of mass destruction (WMDs) who serves as a consultant for the US Defense Department, Department of Homeland Security, and other groups. "I don't care what kind of detector it is. You give me a detector, and I can get it to false alarm to something," Miller said. On the bright side, detectors don't provide false negative, so if the chemical is out there, it will detect it, even if it sometimes mistakes other things for that chemical.

Development thus continues on devices that will be more accurate. The goal with detectors, though, is to have "stand-off" rather than "point" detection, so that the threat can be spotted at some distance away from troops, providing military forces with more time to react. One current stand-off chemical detector, the M21, uses a passive infrared sensor to automatically scan the atmosphere for clouds of nerve- and blister-agent vapors up to 5 kilometers away. But the system needs to be standing still to detect anything. Dr. Kirk Phelps, senior team leader for chemical and biological detection at the US Army's Edgewood Chemical and Biological Center, said that one of the largest clouds of vapor that the M21 might be able to detect causes only about a 1% change in the background radiation, which is what the device is actually measuring, and the typical cloud of agent vapor would be much less concentrated than that.

So several program are in development to make stand-off detection more precise, including the US Joint Service Light Weight Standoff Chemical Agent Detection System (JSLSCAD), which could be mounted on an unmanned aerial vehicle or a helicopter and would scan hundreds of square kilometers for the "spectral fingerprint" of certain chemicals using infrared imaging. But programs like the JSLSCAD, for which General Dynamics division GD Advanced Technical Products (Charlotte, NC) is serving as prime contractor, or the US Joint Chemical Agent Detection system – for which BAE Systems (Austin, TX), Smiths Detection, and several other companies are competing to serve as prime contractor – have reportedly run into delays, though the office responsible for oversight of these programs, the Joint Program Executive Office for Chemical and Biological Defense, did not respond to a request for comment.

To the Rescue

Many military forces and civilian law-enforcement and firefighting organizations address the problem of biological and chemical agents by forming units specially trained to cope with emergencies. The US Marine Corps' Chemical Biological Incident Response Force, for example, is headquartered in Indian Head, MD, and has been predeployed to a number of events, such as the 1996 Atlanta Olympics and the presidential inaugurations of 1996 and 2000. The 161-member team is trained to operate various types of detection equipment and deal with situations like the cleanup of the mailroom of the US Senate majority leader, who was sent mail containing ricin.

Internationally, NATO countries in 2003 created a multinational force called Chemical, Biological, Radiological, and Nuclear Defense battalion, with 500-700 people and various technologies and other resources contributed by various nations. But the battalion is intended to be able to mobilize within five to 20 days. Because time is of the essence in biological and chemical attacks, especially the latter, teams trained in dealing with hazardous materials aren't much good unless they are close by, noted Mark Allen Miller, a former US Army officer who is now a consultant for the Defense Department and other groups on dealing with weapons of mass destruction.

"There are lots of hazmat [hazardous-material] teams across the country that have detectors that can be deployed. But in reality, it's not possible to protect every single ballgame or every single school," he said. "They need to be deployed where there's a perceived threat so they can detect if something has happened."

Mobile Laboratories

Typically, specialized units have been created to keep an eye out for biological and chemical threats. The UK Ministry of Defence, for instance, in December 2003 received its first six Integrated Biological Defence Systems (IBDS) – four-ton Leyland Daf trucks that carry a biological-detection system, communications, and meteorological equipment. Four people ride inside each vehicle, the interior of which can be shut off from the outside environment. Chris Martin, head of marketing and public relations for Insys Ltd. (Ampthill, Bedfordshire, UK), the prime contractor for the IBDS program, said the vehicles have been used extensively in the Middle East and can operate in a fully "battened down" position for a number of hours, as the crew members operate the detection equipment. Delivery of a total of 50 is expected to be completed late next year, Martin said.

The US Army and Marine Corps operate 120 Fox reconnaissance vehicles – one of which is shown here – that are equipped for chemical detection and analysis. A new vehicle intended for use with the Army's Stryker brigades will also be able to detect biological agents, provided development programs stay on track.

Similarly, the US Army and US Marine Corps operate 120 Fox reconnaissance vehicles, developed by General Dynamics Land Systems (Sterling Heights, MI) and Thyssen Henschel (Kassel, Germany), which cannot do any biological detection but do come equipped with the M21 detector and an MM-1 Mobile Mass Spectrometer for chemical detection and analysis. A vehicle called the NBC RV, which would include the JCAD and JSLSCAD detectors, is intended to replace the Fox starting in 2006. This would form part of the US Army's planned Stryker brigades, which are intended to take advantage of better communications and battlefield intelligence to allow vehicles to be more lightly armored and, thus, move more quickly.

Dr. Kent Harding, chief scientist at Defence Research & Development Canada – Suffield, which trains biological- and chemical-response teams from around the world, noted that these types of detection vehicles, in which the occupants might drive themselves into the middle of an area possibly contaminated with chemical or biological agents for the purpose of collecting samples, literally putting themselves in harm's way despite the protection the vehicles are designed to provide against the outside air, represent an approach to agent detection that scientists hope to make obsolete through development of better stand-off detectors. "Currently, with detectors the material is upon the detector before it makes a detection," Harding said. "So you want to push that out as best you can, either by forward deploying a number of smaller, cheap detectors, which can just alarm when the cloud go over them, or something that can interrogate the air forward of your position."

A member of the Irish Guards stands watch in Basra as smoke rises from nearby oil well fires. Smoke and diesel exhaust frequently set off chemical detectors deployed during the 1990-1991 Gulf War, and experts say that false alarms continue to be a problem for detection technologies.

The problem with biological detectors is that the processes required for identifying agents really need to be done by trained people, though automation within some systems does permit the detectors to make what is basically a rough guess as to what the agents are. Stand-alone detectors that are currently fielded include the Portal Shield, which was first deployed during to the Persian Gulf during Operation Thunder in 1998 and of which more than 150 units have been deployed to date at various military locations. Roughly one-third the size of an office desk, the Portal Shield, made by Sentel (Alexandria, VA), is basically a miniature biological laboratory that collects air samples, concentrates them, and determines whether biological agents are present by comparing the samples with "assay strips" treated with antibodies that react to particular agents. The device can photograph the results and transmit the picture to operators, who then get an initial idea of what the threat may be, though solid confirmation of the agent generally requires someone actually going to the Portal Shield and retrieving the sample for lab testing.

Biological detectors, in comparison with chemical detectors, simply cannot provide very reliable instant identification of an agent. They can detect that something is there, but initial identification takes perhaps 15-20 minutes. With anthrax, as with generally all biological threats, the sooner treatment begins, the better off the victim is. But unlike chemical agents, which affect people almost instantly, biological agents take much longer to have an effect on people, so even if a detector cannot immediately identify an agent, it still has a lot of value. Sentel CEO and President James F. Garrett uses the example of a football game where biological sensors pick up the presence of anthrax. Although operators of the sensors may not know immediately what agent the detectors discovered, the detectors at least allow authorities to get an idea of who may have been affected before the agent's full effects hit. Then authorities can make announcements to that effect that, everybody at last night's Washington Redskins or Real Madrid game should seek treatment at designated locations.

Fast Reaction

But by networking multiple sensors together – including nuclear, chemical, biological, seismic, and more – those responsible for ensuring the security of military encampments and permanent bases, as well as civilian locations like airports, power plants, sports stadiums, and so on, can get much more information about the nature of a breaking crisis. By networking together multiple sensors using software like Sentel's Remote Data Relay or BAE Systems' HazSentry, authorities know that, if a biological alarm is triggered in one area, then another biological alarm nearby is also triggered, the odds are much higher that this is not just a false alarm, and the size of the direction of the threat is more easily understood.

By linking, for instance, surveillance cameras to biological or chemical alarms, operators of such systems can immediately look at an area where an alarm has been triggered and plan a more nuanced response. Say a chemical alarm near a subway station is triggered, but cameras do not show anyone falling down and getting sick. Authorities might make a more measured response. "But if you see people falling, choking, and all that, then you know there's something there and that you don't want to rush 'first responders' in there unless they have protective gear," Sentel's Garrett said.

DRDC-Suffield's Harding said that the latest generation of bio detectors – which are still in development – employ fluorescence detection. A laser within the device excites the molecules of air passing through, and since the molecules of living organisms fluoresce at characteristic wavelengths, particular bacteria and viruses can be identified based on their fluorescence. Additionally, a particle-sorting device within the system helps determine the concentration of the agent and verify its composition. Systems can either do the identification process automatically, or prepare a sample that a person can retrieve from the system and take to a laboratory (perhaps a mobile lab nearby) for analysis. In addition, work is being done to use light-emitting diodes (LEDs) instead of lasers in these systems, which should make them smaller, lighter, and cheaper, Harding said.

What about new biological threats that emerge, developed perhaps by scientists who splice together the DNA of different organism? Detectors will need to be updated to handle those, but how can scientists instruct a machine to recognize something they themselves have never seen before? Defense departments already face a huge problem in attempting to detect and identify the very small amounts of material in the air that could be biological agents. Edgewood CB Center's Phelps noted that 1,000-times-less biological compared with chemical material might be required to cause widespread harm. A magic box that can reliably spot such material may remain a similarly hazy, far-off prospect for some time to come.

10,279 Posts
Fascinating article. We are all in danger to some degree but there is nothing the average citizen can do. I'm glad that they are making improvements to the detectors our soldiers use in the battle zones. Thanks Garand.


9,586 Posts
Discussion Starter #3

Premium Member
1,118 Posts
The bottom line on biological agents is that unless there is prior info, or unless detection units are in place throughout our country, there is nothing to detect them in time.
1 - 4 of 4 Posts