PROPOSED REVISIONS TO NEW SOURCE PERFORMANCE STANDARDS
(NSPS) FOR NITRIC ACID PLANTS
• On September 30, 2011, the U.S. Environmental Protection Agency (EPA) proposed to
strengthen air pollution limits for nitric acid plants. Most nitric acid is used to produce
• The proposed standards, known as New Source Performance Standards (NSPS), would limit
emissions of nitrogen oxides (NOx) from new, modified, and reconstructed nitric acid plants.
NOx is a key ingredient in the formation of ground-level ozone (smog). It also contributes to
the formation of fine particle pollution.
• Currently, the NOx emissions limit is 3.0 pounds of NOx per ton of nitric acid produced. The
Agency is proposing to lower the limit to 0.50 pounds NOx per ton of nitric acid produced.
EPA estimates that this proposed rule would reduce NOx emissions from these facilities by
2,000 tons per year.
• Nitric acid plants are likely to use selective catalytic reduction (SCR) as the control
technology to meet these limits.
• There are an estimated 40 nitric acid plants in the US. This rule would only apply to those
facilities if they modified their production facilities. EPA estimates that six new facilities
will come on line over the next 5 years and be subject to these requirements.
• EPA will take public comment on the proposal for 45 days following publication in the
Federal Register. EPA will hold a public hearing, if one is requested.
EPA Fact Sheet: