ONE-STOP SOLUTION FOR EPA METHOD 325

Importance of the Topic

EPA Method 325 A/B represents a critical regulatory update requiring continuous fenceline monitoring of volatile organic compounds (VOCs) at U.S. petroleum refineries by the end of 2017. Benzene and other hazardous air pollutants such as 1,3-butadiene, toluene, ethylbenzene, and xylenes must be quantified at refinery boundaries to protect public health and comply with CFR 40 parts 60 and 63. Establishing reliable, high-throughput analytical workflows is essential for meeting stringent performance standards and maintaining regulatory compliance.

Study Objectives and Overview

This application note outlines a complete turnkey solution for EPA Method 325, from field sampling through laboratory analysis and data reporting. Collaborating with the U.S. EPA during method development, PerkinElmer provides an integrated approach combining optimized passive sampling, thermal desorption, and gas chromatography-mass spectrometry (GC/MS) to streamline complex monitoring requirements.

Methodology and Instrumentation

Field sampling employs passive sorbent tubes housed in protective shelters at refinery fencelines. Key instrumentation includes:

• TurboMatrix ATD: automated thermal desorption with tube conditioning, sorbent compatibility, compact footprint, and rapid cycle times.
• Clarus SQ 8 GC/MS: high-sensitivity quadrupole MS detector, fast oven ramp, Marathon filament for enhanced uptime, and TurboMass software for environmental reporting.

Sampling schedules depend on refinery size, ranging from 12 to 24 primary samples per two-week period, plus duplicates, near-source locations, and field blanks. Automated desorption and bar-coded tube tracking ensure traceability and efficiency.

Key Results and Discussion

A standard chromatogram achieved baseline separation of benzene, toluene, xylenes, and trimethylbenzenes in under four minutes. This rapid analysis enhances laboratory throughput while maintaining detection limits well below regulatory thresholds. The integrated system supports continuous sampling, analysis, and data management to generate a traceable audit trail.

Benefits and Practical Applications of the Method

PerkinElmer’s solution delivers:

• Turnkey compliance package: shelters, sorbent tubes, ATD, GC/MS, software, training, and support.
• High sensitivity and fast cycle times for TD-GC/MS analysis.
• Automated handling and bar-coded tracking to reduce manual errors.
• Scalable sampling plans tailored to refinery size and operational requirements.

Future Trends and Possibilities

Emerging developments may include real-time VOC sensors integrated with wireless networks, advanced data analytics for predictive emissions monitoring, and miniaturized desorption-GC platforms. Continued innovations in sorbent materials and detector technologies will further improve sensitivity, reduce cycle times, and lower operational costs.

Conclusion

EPA Method 325 compliance presents operational challenges for petroleum refineries. PerkinElmer’s collaboratively developed, fully automated sampling and TD-GC/MS analysis workflow offers a robust, high-throughput solution that meets regulatory requirements and simplifies complex monitoring programs.

Reference

PerkinElmer, Inc. Application Note on EPA Method 325 A/B compliance.