Gas mask sensor
Engineers at Carnegie-Mellon University in Pittsburgh have developed a sensor to alert firefighters and emergency responders when it is time to change the cartridge in their gas mask. These teams rely on gas masks to protect them from dangerous toxins. Breathing respirators protect against toxic gases, and cartridges on the respirator filter the air. Over time, the cartridges need to be changed, and without knowing it users could be inhaling deadly gases. They currently have no good mechanism for knowing when their carbon cartridges in their respirators are spent. The tiny sensor fits inside the cartridge would monitor when it became saturated with dangerous gases. It would act like an "electronic nose," sorting and identifying the chemicals present, because its chip is imprinted with a special conductive polymer coating that is sensitive to differences in chemicals. After the electrodes are surrounded by the gas, each electrode reacts to a particular substance by changing its electrical resistance. Back at the fire station, the speed of the wires on the sensor is checked. If the wires have slowed down -- that's a warning the cartridge needs to be changed before the next fire. It can save long-term health of first responders. It's going to be another safety net for them.
Source: ivanhoe.comAdded: 3 January 2007