FEAT Emissions by Stedman

Today's discussion of auto emissions prompted me to look up Stedman's system, FEAT, for more information on implementing and enforcing it. According to the website:

The FEAT was designed to emulate the results one would obtain using a conventional garage-type exhaust gas analyzer. An infrared and ultraviolet source are shined across a roadway onto multiple detectors which detect changes in the atmospheric concentrations of carbon dioxide (CO2), carbon monoxide (CO), unburned hydrocarbons (HC) and nitric oxide (NO) before and after the vehicle. A video picture of the back of the vehicle is simultaneously recorded. Because the effective plume path length and amount of plume seen depend on a number of factors the FEAT reports mass ratios of CO, HC, or NO to CO2 or gram of pollutant/kg or gallon of fuel consumed. Using these measured ratios as inputs to a standard combustion equation for gasoline many components of the vehicle operating characteristics can be determined including the instantaneous air/fuel ratio and the %CO, %HC, and %NO which would be read by a tailpipe probe.

The site also contains examples and reports on the system, including claims that "This system is currently the most cost effective method for obtaining a mobile source inventory for a city or region." There are also statistics on FEAT's margin of error.

The video system seems to be a better alternative than simply mounting FEAT on police vehicles, for the same reason automated radar systems are better at catching speeders than a parked police car. If someone sees a police car, they are likely to slow down. This reduces their emissions, providing a low-end reading instead of the higher-end one from when they create more air pollution.

The random nature of testing also provides better motivation for drivers to be aware of their emissions than yearly emissions tests. There are several psychology articles on different types of behavior reinforcement; here is one that is fairly straightforward and easy to read. Randomly placing and using FEAT is a good example of a Variable Ratio schedule of reinforcement as discussed in this article. Basically, the motivation to be aware of emissions is similar to the motivation to gamble, and it's a powerful one in human psychology.

While FEAT seems like an interesting idea, there are still several problems with implementing it. It doesn't discuss the problem of fining out-of-area vehicles, which vehicles have different requirements (as some do in the emissions-testing areas of Utah, for instance), or what happens if a vehicle does not have a clearly visible license plate or identification (or any at all) and they cannot be ticketed. Do we want to punish drivers who have license plates?