What are NOx emissions standards?

Nitrogen Oxides, commonly referred to as NOx, is a family of poisonous gases. These gases are best known for their role in air pollution, leading to occurrences of acid rain, smog, and the deterioration of the ozone layer.
In short, NOx is harmful to the atmosphere and the environment and needs to be limited as much as possible.
The problem is that NOx is quite common. It's created as a result of fuel burning at high temperatures. Cars, trucks, boats, and other kinds of vehicles emit NOx almost constantly. Industrial sources like industrial boilers, turbines, and power plants are also responsible for releasing poisonous NOx into the air.
Obviously, regulating NOx emissions as a result of private vehicles is nearly impossible to enforce, aside from encouraging people to use more fuel efficient vehicles. However, doing so for stationary sources of NOx is more feasible, which is what the Clean Air Act of 1990 set out to do. As a result, many companies must adhere to NOx emission standards to ensure that they are limiting the amount of pollution they release into the air as much as possible.
NOx emission standards are based on Reasonably Available Control Technology (RACT), which takes into account economic and technological factors when determining an emission level that's fair and reasonable. The EPA has a hand in determining emission regulations for each state, and once the EPA is satisfied with each state's plan for emissions reduction, it will approve a State Implementation Plan (SIP) for each state.
While private citizens can make certain lifestyle changes to reduce their own NOx emissions, facilities that release NOx in much larger quantities can do even more to reduce their scourge on the environment. For instance, there is equipment that can help to control air pollution, including selective non-catalytic reduction or selective catalytic reduction. Modifications can also be made to the combustion process that result in lower NOx emissions that help to meet the necessary restrictions.
Companies like industrial boiler manufacturer ZOZEN are doing their part to help meet emission standards. ZOZEN's boilers are not only more energy efficient, but their industrial boilers meet lower NOx standards, something that can go a long way toward protecting the atmosphere and the environment.