Grantee Research Project Results
Final Report: Open Path Analyzer for Accurate, ppt-level Quantification of EtO via Mid-Infrared Cavity Enhanced Spectrometry
EPA Contract Number: 68HERC22C0037Title: Open Path Analyzer for Accurate, ppt-level Quantification of EtO via Mid-Infrared Cavity Enhanced Spectrometry
Investigators: Gupta, Manish
Small Business: Nikira Labs Inc.
EPA Contact: Richards, April
Phase: II
Project Period: January 1, 2022 through December 31, 2023
Project Amount: $400,000
RFA: Small Business Innovation Research (SBIR) Phase II (2022) Recipients Lists
Research Category: SBIR - Air , Small Business Innovation Research (SBIR)
Description:
In this highly successful SBIR Phase II effort, Nikira Labs Inc. has developed a highly-precise instrument for ethylene oxide quantification in ambient air. The analyzer utilizes an intraband quantum cascade laser coupled to a high-finesse optical cavity to provide selective, precise, and rapid measurements. The instrument measures only 56 cm x 23 cm x 14 cm, weighs 4 kg, and uses less than 30 W of power, making it ideal for both fenceline and mobile applications.
Summary/Accomplishments (Outputs/Outcomes):
Subsequent to fabrication, the Phase II systems were extensively tested to determine their analytical performance. The analyzers provided a measurement precision of better than 0.1 ppb (1s, 2 Hz). Moreover, they exhibited a highly linear response (R2 > 0.9999) over a wide ethylene oxide dynamic range (0 – 1 ppm), making them well-suited for both trace and source monitoring. The fast response (T90-10 time of ~1 s) allowed for real-time measurements in mobile monitoring and wind-correlation experiments. Additionally, the units were found to have minimal cross interference with common atmospheric constituents (methane and water vapor) and operate over a wide ambient thermal range (5 – 45 °C). Finally, data quality metrics were included to avoid erroneous readings from interfering absorption species.
The fully functional analyzers were deployed for both fenceline-style and mobile monitoring. The former involved measuring ethylene oxide and wind parameters to locate a fabricated ethylene oxide leak akin to the EPA SPOD technique. The latter involved driving the analyzer proximate to a small ethylene oxide sterilization facility and observing several, small ethylene oxide signatures. Due to the analyzers’ ability to simultaneously measure methane, the mobile deployments also found several natural gas leaks.
SBIR Phase I:
Open Path Analyzer for Accurate, ppt-level Quantification of EtO via Mid-Infrared Cavity Enhanced Spectrometry | Final ReportThe perspectives, information and conclusions conveyed in research project abstracts, progress reports, final reports, journal abstracts and journal publications convey the viewpoints of the principal investigator and may not represent the views and policies of ORD and EPA. Conclusions drawn by the principal investigators have not been reviewed by the Agency.