ABSTRACT
Four types of hydrogen detectors are used by researchers, engineers, and manufacturers today, and if hydrogen continues to play a role in emerging alternative energy sources, there will be exponential growth in the use and need for more advanced and more robust devices in the future. The types of sensors reviewed in this chapter are (1) room-temperature hydrogen leak sensors; (2) thermometers, particularly useful at low temperature; (3) liquid hydrogen volume and mass gauges; and (4) para/ortho hydrogen ratiometers.
