Airports have increasingly become the perfect target for terrorist attacks as events in the last few years have sadly demonstrated. Most technological countermeasures focus on detection devices which are aimed at uncovering explosive devices and concealed weapons, whereas there are currently no effective systems in place to detect CBRN threats in airports around the world.
CBRN threats are more difficult and costlier to identify, meaning that they have often received less attention, notably in the case of chemical and biological threats. However, the dangers of a chemical or biological attack should not be underestimated. Terrorists have been using more diverse means to conduct attacks such as the recent truck attacks in Nice and Berlin. The European Union has warned about the high likelihood of ISIS using CBRN weapons to conduct further attacks on European soil. A chemical or biological terrorist attack would also have an important impact way beyond medical consequences for those affected such as the possibility for further contamination. Such an incident would have important psychological, economic and political implications as well, due to the widespread fear and panic chemical and biological agents produce in populations.
Airports embody an ideal target for a biological or chemical attack. They attract large flows of people every day who can spread infection in all four corners of the world. Other elements making an airport an ideal target include the relative ease of access to various locations within airports such as departure/arrival halls, the large number of entry/exit points to access these spaces and the numerous choke-points created by closely aggregated crowds. Additionally, the fact that almost everyone carries luggage conceals any illicit transportation of materials up to security checkpoint areas.
Airports are also enclosed spaces which require heating, ventilation and air-conditioning (HVAC) systems to ensure adequate air quality. These systems, in turn, represent targets for biological or chemical terrorist attacks since agents can be easily dispersed through HVAC technology. Few airports are equipped with air neutralization systems which could remove contaminants since adapting existing facilities to accommodate these systems is very costly. An agent released into an air duct would be dispersed into all connected spaces and affect a large number of people. Yet, the severity of such an attack depends on the quantity of agent used and the quality of the air filtration system.
Releasing an agent into the air is a very effective method to contaminate a larger number of people, but it is not the only method. Given the large number of shared spaces at airports, such as bathrooms, elevators, shops, restaurants or praying rooms, there are other possible delivery methods such as contaminating water or food supplies, or spreading the agent on frequently touched surfaces.
Biological or chemical agents have so-far not been successfully used during terrorist attacks targeting airports. Still, chemical and biological agents offer a number of advantages, namely the variety of dissemination methods for certain agents, the relative ease in which they can be obtained, the lack of early warning systems and the delayed effects in the spread of chemical or biological agents. Moreover, terrorists usually seek to induce fear and chaos, which such an attack would certainly achieve.
Anthrax, for instance, has been used as a bio-weapon in the past, can be found in nature or quite easily produced in a lab. It can be used in powder or spray form, in food or water, it can be inhaled, ingested or simply touched. The spores which are known to be odorless, tasteless and colorless, are very resistant to destruction and the bacteria can spread easily, making it a very versatile and dangerous bacterium. Symptoms of anthrax can also take several days to materialize, making it harder to detect those who have been infected. In an airport, anthrax could be used in numerous ways ranging from an aerosol spray can released in the departure hall to powdered spores spread on elevator buttons or door handles.
Several strategies exist in the aviation security industry to develop existing CBRN defense capabilities. Some experts focus on improving detection systems within airports taking into account the cost of such technologies, the range of agents that can be detected, the time it takes to detect and identify agents and their use in conjunction with a fast and efficient human response. Others focus on improving HVAC systems, yet, this can be very costly. Lastly, some specialists also put emphasis on optimising preventive measures such as profiling, enhancing security around HVAC systems or increasing security personnel.
Some governments have started to take steps to improve their current defense strategies against CBRN threats within airports. However, given the increase of air travel around the world, the number of new targets will only increase. Furthermore, the diversification and multiplication of terrorist attacks around the world only amplifies the risk that the next attack might involve chemical or biological agents. The question is no longer if, but when.