US EPA extends proficiency testing to the ‘PAMS’ network for organic ‘ozone precursors’

Markes – Agilent thermal desorption systems included in the US EPA’s first independent field evaluation of the US ‘PAMS’ network.

In response to the 1990 Clean Air Act Amendments the US Environmental Protection Agency (US EPA) introduced provisions for enhanced monitoring of ozone and its precursors, including volatile organic compounds, in many major cities and population centres across America. The US network of Photochemical Assessment Monitoring Stations (PAMS) has now been operating for over 20 years, with multiple online thermal desorption – gas chromatography (TD–GC) systems monitoring street-level air quality around the clock throughout the summer months. The data produced has contributed to steady improvements in urban air quality over time.

Despite the challenges presented by field monitoring stations, rather than fixed laboratory locations, US EPA has now initiated a successful proficiency testing scheme to evaluate the quality of data produced by the PAMS network.

Managed by Battelle Laboratory, Columbus Ohio on behalf of the US EPA, a total of 28 PAMS sites participated in the first proficiency test which was held last year (2023). It involved reporting a total of 57 volatile organic compounds including 25 priority targets and 32 optional species. Three different makes of ozone precursor monitoring system were in use across the participating network sites and Markes-Agilent TD–GC systems performed exceptionally well.

The results were broadly very encouraging but nevertheless demonstrated the importance of analytical quality assurance schemes like this.

The US EPA is also keen to hear directly from scientists in other countries wanting to set up such a proficiency testing scheme for their own network. Please email me for the correct contact details.