Nerve agents false alarms

Gaseous agent Nerve gas Blister agent Vomit agent Lacrimator False alarm Response time Recovery time Operation... 

The most widely available U.S. military detector for chemical agent vapors is the M256A1 Chemical Agent Detector Kit. These kits contain cards with vials of liquid chemical reagents attached that are combined and exposed to the air in a specific sequence. The kits must be manually manipulated, and the full sequence of tests takes 20 to 25 minutes. These kits are the most sensitive detector of nerve agent vapor and are not subject to the same type of interferents that can cause false alarms in some of the electronic detector systems. 

The SAW Mini-CAD is a commercial available pocket-sized instrument that can automatically monitor for trace levels of toxic vapors of both sulfur mustard and the G nerve agents with a high degree of specificity. It does give false alarms from gasoline vapor and glass cleaner. 

The JCAD will employ surface acoustic wave technology to detect nerve and blister agents. It is designed to be lightweight and portable and will reduce false alarms. The JCAD will also allow detection of new forms of nerve agents. 

The most satisfactory detector deployed in the Gulf War was on the Fox recormaissance system, which is an armoured vehicle with several sorts of detector aboard, including ones that detect radioactivity. The main nerve agent detector, the MMl, is again based on mass spectrometry but it is much more sophisticated than the M8A1, and gives rise to far fewer false alarms. 

The M8A1 Automatic Chemical Agent Alarm electronically monitors for hazardous levels of nerve agent vapor. While sensitive, it is also prone to false positive responses due to high concentrations of various organic compormds including some pesticides and vehicle exhausts. Operators must be trained to use care in emplacing the device to minimize the chance of false alarms. 

Surface Acoustic Wave (SAW) sensors detect changes in the properties of acoustic waves as they travel at ultrasonic frequencies in piezoelectric materials. The basic transduction mechanism involves interaction of these waves with surface-attached matter. Multiple sensor arrays with multiple coatings and pattern recognition algorithms provide the means to identify agent classes and reject interferant responses that could cause false alarms. Acoustic wave sensors are used in mobile detectors to detect nerve and blister agents. 

Figure 9.41 displays a DMS vapor detector, battery powered, weighing only 2 lb. Use of DMS mode improves sensitivity and allows it to be tuned to detect specific compounds, improving selectivity and allowing it to detect trace levels with fewer false alarms. It can monitor most chemical warfare agents, particularly the five major nerve agents, and toxic industrial vapors such as HCN, CI2, H2S,... 

In 1990, the Iraqi Army invaded neighboring Kuwait. Subsequently, the United States, at the request of Saudi Arabia, led a coalition to send forces to the area (Smart, 1997). These forces were the largest to operate in a potential chemical environment since World War I. They were provided witii atropine autoinjectors, an acetylcholinesterase reactivator, and a nerve agent pretreatment (p5nidostig-mine bromide). Fortunately, chemical weapons apparently were not used in this conflict, although multiple false alarms were reported. The failure of the Iraqi military... 

Gaseous Agent Nerve Gas Blister Agent Vomiting Agent Lachrymator False Alarm Response Time Recovery Time Operation... 

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