Safety

The detection of explosive conditions in hydrogen applications is important for both safety and economic reasons. Cost-effective hydrogen sensor technologies that deliver detection selectivity and sensitivity, dependability and durability, stability and reproducibility, resistance to chemical degradation and real-time response are needed. An examination of the commercially available point-contact hydrogen sensors indicates the majority of these sensors fall into four main categories: catalytic combustion, electrochemical, semi-conducting oxide sensors and thermal conductivity detectors. All of these sensors depend on the interaction of hydrogen with palladium (Pd) or Pd-based alloys.

One kind of hydrogen sensor being developed at FSEC is "Smart Paint." Smart Paint is a special powder that can be painted onto the surface of field lines, flanges, and joints of hydrogen pipelines or vessels to detect minute hydrogen leaks. The paint provides a visual method to detect and locate possible hydrogen leaks that may occur.

Vehicle applications require the development of new sensors with capabilities beyond those of commercially available systems. Areas of most interest include micro-machining and micro-fabrication technology to fabricate miniaturized sensors. In addition, new techniques that allow control and interrogation of each sensor and provide self-calibrating capability are needed.