Within the revised 1997 National Ambient Air Quality Standards Monitoring Program for particulate matter less than 2.5 micrometers (PM-2.5), the EPA is implementing a "Supersites" monitoring program designed to conduct special, detailed chemical and physical characterization studies in geographic areas. One of the required analytical techniques for 24-hour integral filter samples is particulate organic and elemental carbon (OC/EC) by a thermal/optical method. For improved time resolution of this measurement in the "Supersites" and other time-resolved exposure programs, Sunset Laboratory proposes to develop a new, commercially viable, real-time in situ OC/EC instrument. Initial design and performance validation will be based on a previously described prototype. Phase I is designed to optimize the instrument sensitivity and reliability through a series of design improvements. It will incorporate the latest in electronic and optical developments along with an optimized oven and detector design for improved, reliable field operation. The resulting device is projected to have a minimum time resolution of 30 minutes with minimum quantifiable levels of 0.5 g/M3 each of organic and elemental carbon.The Phase I effort focuses on the implementation of basic instrument optimization and performance upgrades. The effort is designed primarily to optimize the sensitivity through a series of design improvements such that the instrument is capable of routine performance with 30-minute time resolution and minimum quantifiable levels of 0.5 g/M3 each of organic and elemental carbon. Reasonable steps to validate the instrument performance are proposed. Phase II will focus on the implementation of the embedded controller system and nonquartz oven design as well as finalizing the external configuration of the instrument for field service and market appeal. Commercial applications include short- and long-term OC/EC monitoring and EPA Supersite support. Other interested parties likely include universities supporting the PM-2.5 program and investigators performing research in speciated organic measurements and vapor/particle partitioning research. Another potential application is the investigation of PM formation from JP8 jet fuel and subsequent exposure assessment of flightline personnel by the Air Force.Supplemental
Keywords:small business, SBIR, monitoring, engineering
