Approved by the Energy, Environment, and Water Policy Committee on February 17, 2026 
Approved by the Public Policy and Practice Committee on May 27, 2026 
Adopted by the Board of Direction on July 21, 2026

Policy

The American Society of Civil Engineers (ASCE) supports continued control and reduction of pollutants through the Clean Air Act. Specifically, ASCE supports:

  • The setting of national ambient air quality standards to protect public health and welfare. 
  • The establishment of emissions standards for hazardous air pollutants.
  • The implementation of control to reduce or eliminate emissions. 
  • Research into the limit, control, and mitigation of the sources, causes, and consequences of pollutants.
  • Continuous air quality monitoring and measurement.
  • Consideration of atmospheric pollutants within comprehensive pollution management.

Issue 

The Clean Air Act is the comprehensive federal law that regulates air emissions from stationery and mobile sources. The Act was originally passed in 1963 and amended in 1970, 1977, and 1990. The Act contains provisions to:

  • control pollutants using national ambient air quality standards, 
  • control “hazardous air pollutants” or toxic air pollutants, 
  • control acid rain, 
  • protect the stratospheric ozone layer, and 
  • provide for operating permits and enforcement. 

According to the US Environmental Protection Agency, between 1970 and 2018, the combined emissions of six common pollutants (PM2.5, PM10, SO2, NOx, VOCs, CO, and Pb) have decreased by 74 percent, while the U.S. economy has continued to grow. The success of the Clean Air Act has positively contributed to human health, as well as the health of the natural and built environment. 

Rationale

Civil engineers are routinely involved with design, construction, and operation of engineering projects that can generate atmospheric pollutants. Regulations adopted to implement the Clean Air Act can influence permitting, construction methods, transportation planning, industrial facility design, environmental compliance, and other activities undertaken by civil engineers. Atmospheric pollutants, and resulting phenomena such as acid rain, can cause degradation of infrastructure. Mitigation of atmospheric pollutants is not only important for human health and the natural environment, but it can also protect the built environment. Ongoing monitoring and mitigation of atmospheric pollutants is essential to continue the progress achieved since the enactment of the Clean Air Act.

This policy has worldwide applications 
ASCE Policy Statement 285
First Approved in 1982

See also Policy Statement 362 Comprehensive Pollution Management