Supporting Safe, Comfortable and Efficient Design.

We believe in sustainable design, which can be achieved by protecting the environment while benefiting society and the economy. We work to preserve and enhance air quality while promoting a healthy economy.

There are two general ways we can help:

1. Advanced Air Modeling Services

The Clean Air Act (CAA) was established by Congress to protect public health and welfare. As a result of the CAA and more recent air regulations, there has been a significant decrease in air pollution in the country.

However, air quality regulations, such as the National Ambient Air Quality Standards (NAAQS), have become more complex and stringent in the last few years, posing a significant challenge to economic activity.  For example, the recent short-term NAAQS are much more difficult to meet than the original longer-term standards. This is because the conservative assumptions in AERMOD, EPA’s accepted regulatory model, are more critical when dealing with these very stringent short-term standards. Many studies have shown that the results from AERMOD significantly overestimate ambient concentrations.  Some of the currently-used assumptions that can cause significant overpredictions  include:

  • Unrealistic building downwash effects calculated by the Building Profile Input Program for PRIME (BPIP) used by AERMOD
  • Assuming continuous maximum emissions
  • Pairing maximum background concentrations with the modeled (predicted) values
  • Simplistic haul road characterization
  • Inappropriate wind speeds to characterize wind-blown dust from storage piles
  • Inappropriate friction velocity to characterize low-speed winds under stable conditions


If your project has stalled because of modeling requirements or if you need an alternative to less-accurate, overly-conservative modeling methods, we have scientifically-based, validated alternatives that can support your project while protecting air quality. Some of our advanced modeling services include:

Read more about our advanced air modeling services.

2. BPIP Diagnostic Tool

Read more about our BPIP Diagnostic Tool.

CPP has the unique knowledge, experience, and tools to help you navigate the complex air modeling process.