Open-Path UV Air Monitoring Systems to Replace Passive Diffusive Tubes Using EPA Method 301

Air Monitoring, Methods, and Technology
Oral Presentation

Prepared by E. Stevenson1, B. Olive2
1 - Argos Scientific, Inc., 3620 SE SUNRISE DR (Optional), Camas, WA, 986079419, United States
2 - University of North Alabama, DEPT OF CHEMISTY & IND HYGENE 1660 Tune Ave, FLORENCE, AL, 35630, United States

Contact Information: [email protected]; 503-421-0228


On December 1, 2015, the EPA finalized the Risk and Technology Review for petroleum refineries. Among other things, the finalized rule requires petroleum refineries to conduct fence-line monitoring on a continuous basis. Benzene is the target compound, and an annual-average action level of 9 µg/m3 was established, triggering a refinery lead root cause analysis and corrective action. The fence-line monitoring provisions, found in 40 CFR 63.658, describe the use of a network of passive diffusive tube samplers placed along the refinery’s boundary as the primary method for detecting fugitive emissions of benzene.
The fence-line monitoring provisions allow a refinery owner or operator to submit a request for an alternative test method, such as open-path instrumentation. The use of this type of technology presents the opportunity to meet the requirements of the rule in a more simplified, cost-effective way, while offering advantages in terms of potentially identifying and eliminating data points that correspond to outside emission sources. Such a system also has the advantage of greater time resolution for the data, allowing the presentation of information in near real-time. A field validation study has been conducted using latest-generation, open-path UV-DOAS technology manufactured by Argos Scientific to detect benzene, toluene, ethylbenzene, and xylene (BTEX) gases at a refinery fence line on a continuous basis. The data from the system is compared to an array of passive diffusive tubes placed along the beam path of the open-path UV system. The goal of the study is to develop best practices documentation, including the advantages Argos has with QA/QC when compared to other open-path UV air monitoring systems. Critical to this document is also ensuring it contains all information necessary for California, South Coast and Bay Area Air Quality Management Districts to require its adoption as fundamental, technical assistance to achieve standardized, high quality data.