Chemical detection (and incident notification) systems can provide early, high-confidence warnings in the event of a chemical release. These rapid warnings provide substantial benefits in situations where the chemical released can have an immediate impact on the health of exposed individuals. Detection systems also provide first responders with an awareness of the scale of the incident and the nature of the chemical hazards involved.
Chemical detection technologies can detect chemicals and record their concentrations. Hundreds of chemical detection technologies produced by dozens of manufacturers are available, covering a wide range of target chemicals, detector characteristics and capabilities. Detectors vary in size/weight, the state of material they can measure (solid, liquid, or gas), the number and type of chemicals they can detect, and their operational simplicity, including their ability to operate continuously and autonomously. Some can detect unknown chemicals, alerting the user to the presence of a contaminating substance. The most robust technologies can repeatedly measure tens or hundreds of chemicals over a large area with great sensitivity, selectivity, and accuracy, often within seconds while also recording other relevant data; however, these highly sensitive instruments are often not transportable to a field site.
Two types of detectors exist in terms of how data are analyzed and output provided: real-time field sensors, which provide immediate readings on site, and sampling devices, which collect/ store samples for follow-on analysis in a laboratory. The digital, instantaneous nature of field detector results is a major boon in chemical incidents when response time is of the essence, while laboratory analysis of collected samples may be critical to identifying an unknown released substance.