Putting Houston's Air Quality in Context

The Federal Government has established six National Ambient Air Quality Standards. Houston's air meets five of the six NAAQS. The one standard that Houston is still working to attain is ground-level ozone. For more information about the NAAQS, visit the EPA's website: http://www.epa.gov/air/criteria.html

The quality of Houston's air compares favorably with other cities when looking at all the NAAQS. According to EPA data, Las Vegas, Philadelphia, Pittsburgh, Phoenix, Los Angeles, New York, Sacramento, and Salt Lake City fail to meet two or more of the NAAQS.

Through concerted effort and investment, Houston has achieved an 80 percent reduction in key Volatile Organic Compounds in the past 20 years. While great strides have been made, industry have invested between $4 and 6 billion by 2009 to make further improvements in air quality. This investment is in addition to the substantial investment made in the 1990s.

The 2009 ozone design values for all Houston area regulatory ozone monitors were below the 1997 8-hour ozone standard of 0.08ppm. The Houston area attained this standard for the first time since ozone levels have been tracked in the mid 70's.

back to top

Effects Screening Levels

• ESLs are established by TCEQ based on data concerning health effects, odor, nuisance potential, vegetation impacts, and corrosion effects
• ESLs are not ambient air standards, but are primarily used by TCEQ in evaluating applications for air permits
• Concentrations at or below the ESLs indicate no adverse health or welfare effects are expected
• Concentrations above the ESLs do not necessarily indicate a health effects problem, but trigger a more in-depth permit review

• Almost all monitored VOCs are below their annual ESL; most are a small fraction of their annual ESL
• The one exception is the level of benezene at two monitoring sites. Across the network, more than 99 percent of the benzene readings are below the 24-hour ESL. Overall, benzene levels have decreased more than 80 percent over the past 20 years
• Benzene levels in Houston are comparable to other US cities

back to top

Our Mission Going Forward:
Maintaining and Improving Air Quality

Our on-going mission is to provide data to member companies to enable them to meet state and federal air standards. By using HRM data, our member companies can identify air control improvement projects.

Our member companies are working with the Texas Commission for Environmental Quality to take advantage of HRM member companies working with TCEQ to develop and implement  the Environmental Monitoring and Response System (EMRS) at the Lynchburg Ferry monitor. The program in concert with the Monument Area Air Quality Focus Group (MAAQFG) has resulted in a 70% reduction of ambient benzene levels at the Lynchburg Ferry since 2006. This has prompted the TCEQ to remove the Lynchburg Ferry monitoring site from the benzene air pollutant watch list in 2009.

back to top