A hydrogen sensor is a device that can detect the presence of hydrogen. Because hydrogen naturally exists in the atmosphere in very small amounts, about 0.00005% of the volume, these sensors are designed to detect quantities that might be considered dangerous. Gas detectors used to monitor hydrogen are most commonly used to detect leaks of this gas in closed systems. Hydrogen sensors have also found a niche in the nascent but growing hydrogen fuel cell industry.
Many of the technologies for hydrogen sensor design are in use today. Most people take advantage of the fact that hydrogen is quite chemically active. For example, one type of sensor utilizes palladium. When palladium comes into contact with hydrogen atoms, it spontaneously forms a compound called palladium hydride that is less conductive than pure metals. The concentration of hydrogen in the air can be calculated by measuring the change in the palladium conductivity in the sensor. Advanced hydrogen sensors can be very small, measured in fractions of millimeters or inches, and can detect hydrogen concentrations as low as five parts per million in seconds.
Hydrogen is potentially dangerous. At concentrations above 40,000 PPM, it can be flammable and even explosive. The famous explosion and burning at Hindenburg in 1937 proved just how dangerous the gas could be. Thirty-six people were killed when a large airship filled with hydrogen caught fire, exploded and crashed to the ground. The accident’s fame caused the airship to fall out of favor due to transportation. Because of this and other incidents involving fires and explosions, hydrogen sensors have been deemed necessary as a safety measure.
In 2011, hydrogen sensors are likely to be used in one of three applications. Portable hydrogen sensors are gas detectors that inspectors or technicians can use to spot check any system that holds, transmits or exploits hydrogen leaks. These sensors are typically small, hand-held devices that can be specialized for hydrogen detection or multiple gas detectors that can detect several types of gas depending on Settings.
Static hydrogen sensors may be placed in buildings or other enclosed Spaces. This type of hydrogen sensor works in the same way as a handheld device, but is linked to some type of monitoring system, which may include alarms. In these applications, hydrogen sensors are used to detect a buildup of gas above normal atmospheric levels before it becomes dangerous.
Hydrogen fuel cells are an emerging field of technology that essentially uses hydrogen as a fuel.When burned under controlled conditions, hydrogen provides a lot of energy and is the ultimate green fuel because the byproduct of hydrogen combustion is pure water. Many companies are working on vehicles powered by these batteries. Hydrogen leaks in fuel cells can also be dangerous, and hydrogen sensors are installed in any vehicle, machine or device powered by hydrogen fuel cells.