Open Path Analyzer for Accurate, ppt-level Quantification of EtO via Mid-Infrared Cavity Enhanced Spectrometry

EPA Contract Number: 68HERC21C0016
Title: 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: I
Project Period: March 1, 2021 through August 31, 2021
Project Amount: $99,699
RFA: Small Business Innovation Research (SBIR) - Phase I (2021) RFA Text |  Recipients Lists
Research Category: Small Business Innovation Research (SBIR) , SBIR - Air Monitoring and Remote Sensing , SBIR - Air Quality


In this Small Business Innovative Research (SBIR) effort, Nikira Labs Inc. proposes to utilize open-path, mid-infrared cavity enhanced absorption spectrometry to develop a sensitive (< 10 ppt), fast (< 100 seconds), and highly-selective ethylene oxide (EtO) analyzer suitable for field-deployment. The US EPA has concluded that EtO, which is widely used in ethylene glycol production and medical sterilization, is carcinogenic to humans and assigned it a total inhalation unit risk of 3.3 × 10-3 μg/m3 (~12 ppt). At current levels of control, the carcinogenic risk of EtO is too high, and new amendments to the 2003 Miscellaneous Organic Chemical Manufacturing National Emission Standards for Hazardous Air Pollutants (NESHAP) will most likely require significantly improved EtO monitoring. Current monitoring techniques (e.g. EPA Method TO-15) only provide infrequent, single measurements (grab samples) and may be confounded by interfering compounds including trans-2-butene and acetaldehyde.

In this Phase I, Nikira Labs Inc. will fabricate a mid-infrared cavity-enhanced absorption system that consists of a quantum cascade laser coupled into a high-finesse optical cavity in an incoherent fashion. By using a novel cavity geometry and coupling methodology, the system noise can be significantly reduced. Moreover, by using an open-path cavity, there are no “wetted” materials and no sample handling losses. Subsequent to the prototype development, the analyzer will be extensively laboratory tested on EtO standards to empirically determine its analytical performance (accuracy, linearity, precision, time response…). Potential cross interferences will be measured, and a trial field- deployment will be used to identify Phase II improvements. In addition to its utility for next-generation environmental monitoring, a sensitive, real-time EtO analyzer also has commercial utility in the medical sterilization and petrochemical markets. A preliminary analysis of these markets suggests that Nikira Labs Inc. can realize a 5-year revenue exceeding $7.8M for these two applications alone.