What EPA Method 325 A/B Means For Oil Refineries

Importance of the Topic

Benzene is a known carcinogen and a representative volatile organic compound in crude oil refining. Accurate fenceline monitoring helps protect public health and ensures regulatory compliance with the Clean Air Act.

Objective and Overview of the Article

This article presents an interview with Lee Marotta from PerkinElmer, focusing on EPA Method 325 A/B, a new federal regulation requiring oil refineries to monitor benzene at their fencelines starting in late 2017. The discussion covers method development, field deployment, and analytical procedures.

Methodology and Instrumentation

• EPA Method 325 A: Defines placement of passive sampling shelters along the refinery fenceline at 20° intervals, using inert adsorbent tubes to collect air over a 14-day cycle, including tube cleaning and conditioning.
• EPA Method 325 B: Describes laboratory analysis by thermal desorption–gas chromatography/mass spectrometry (TD-GC/MS) to quantify benzene in collected samples.
• Key Instrumentation: PerkinElmer TurboMatrix Automated Thermal Desorption (ATD) system and Clarus SQ 8 GC/MS.

Main Findings and Discussion

Passive sampling offers long-term, pump-free operation but requires calibration of uptake rates for accurate volume determination. Active sampling provides precise volume control but demands pumps and multi-bed adsorbents. Monitoring data may be influenced by external benzene sources such as traffic or nearby facilities, necessitating source apportionment strategies.

Benefits and Practical Applications

• Helps refineries comply with EPA regulations and demonstrate environmental stewardship.
• Enables early detection of VOC leaks and potential emissions incidents.
• Leverages PerkinElmer’s one-stop solution, including shelters, adsorbent tubes, analytical instruments, and training.

Future Trends and Opportunities

Advances may include continuous real-time monitoring platforms, improved sorbent materials, integrated data analytics for trend prediction, and remote diagnostics to optimize maintenance and reduce downtime.

Conclusion

EPA Method 325 A/B establishes a robust framework for benzene monitoring at refinery fencelines, combining standardized field sampling with reliable TD-GC/MS analysis. Collaboration with experienced instrument and service providers ensures effective implementation and compliance.

References

• Lee Marotta, PerkinElmer, Inc., Interview on EPA Method 325 A/B (2016).
• EPA 40 CFR Parts 60 and 63, Method 325 A and B (effective 2017).