Semiconductor vs Fuel Cell – Know the Facts

When searching for the right ignition interlock, it’s important to know which technology is best, as a positive reading for alcohol can have serious consequences for the user. Debates have surfaced as to whether Semiconductors or Fuel Cells are best suited for delivering accuracy and consistency in alcohol monitoring. As more testing and analysis is conducted using these two technologies the clear favorite has become Fuel Cell.

The LifeSafer FC100 - FC Stands for Fuel Cell
The LifeSafer FC100 – FC stands for Fuel Cell

Although semiconductors have been around longer, and may be cheaper than fuel cell units, they are also less reliable. Semiconductor units do not only react to the presence of alcohol, but also to other substances like cigarette smoke, perfume, hairspray and breath fresheners. The presence of these substances can trigger a “false positive” reading and unduly lead to a false accusation of alcohol use. These units also don’t have a long life span, rarely lasting longer than one year; and they show a wide variation in readings, especially as the units become older or get more use. Lastly semiconductor units detect only the presence of alcohol but cannot quantitatively measure an accurate BAC level. For these reasons no semiconductor device has ever been approved for evidential use (to stand-up in a court of law) by any State Law Enforcement Agencies or the U.S. Department of Transportation. Although a few states, Washington, Colorado and Oregon for example, still allow semiconductor units to be used, this is generally due to the fact that their use was “grandfathered”. Some states, such as Texas and Wisconsin, have banned the use of semi-conductor interlocks due to their poor and inaccurate performance.

Fuel cell units, on the other hand, are calibrated to provide greater accuracy and consistency in testing, are longer lasting (usually 3-5 years) and are alcohol specific in their monitoring, making them much less susceptible to false readings from the presence of other substances. For this reason virtually every new ignition interlock being placed into service is now fuel cell based, even though they cost more than the older semiconductor technology. Fuel cell units are considered the ‘gold standard’ of alcohol monitoring units, and they are the choice of professional Law Enforcement and concerned individuals who require measurement they can trust. When results really matter, the technology that is relied on is always fuel cell.