In a chemical attack (also called chemical agent, or CA, attacks), toxic gases, liquids or solids are released into the atmosphere, either by themselves or in combination with explosives. Agents such as nerve gas or cyanide can poison people and cause significant environmental damage. Chemical detectors are designed either to prevent chemical attacks by identifying chemical agents before their release, or to confirm that an attack has taken place and identify the scope of chemical exposure.
After the September 11 attacks, the United States stepped up efforts to install detection systems in potentially vulnerable sites, such as at borders or in closed areas like rail and subway systems. Systems for use in these areas may use radar detection systems that measure the density of chemicals in the atmosphere; one system being tested combines these with closed circuit TVs to create an entire monitoring system.
Other forms of chemical detection include:
- chemical detection paper;li]
- chemical agent detection kits;
- colorimetric tubes.