Smart Respirators - Embedded detectors for real-time monitoring of end-of-service-life in respirator filter cartridges

Project Summary/Abstract: Respirator masks are worn by workers in many industries, such as oil and gas, metal working, hazardous materials, and chemical research and manufacturing. Common organic vapor (OV) respirator masks employ periodically replaceable filter cannisters or cartridges, costing $5 to $40, depending on level of protection and manufacturer. The service life of a replaceable filter is highly variable, depending on the wearer's lung capacity, type and concentration of chemical exposure, and environmental factors, and may range from minutes to days. Currently there is no definitive means to recognize impending break-down in protection and there are no “smart” filter cartridges capable of reliably alerting the wearer to imminent breakthrough. In this SBIR, Seacoast Science, Inc. is developing embeddable detectors to create new “Smart Respirators”, guided by specifications provided by Honeywell Safety Products, Inc., to detect the end of service life (EOSL) in OV filter cartridges. Honeywell is developing a wireless interface which will interface with the sensors and provide the user with a warning before chemical breakthrough. These real-time detectors will measure concentrations of chemical vapors associated with a wide range of high-risk occupations. This is the first step to creating smart personal-protective equipment for workers in a wide range of chemical industries. Ultimately, data from smart cartridges can be wirelessly linked to an exposure/location mapping system, to help identify operational failures such as chemical leaks, so the workplace can be made safer. In Phase I, Seacoast identified chemosensitive materials applied to various capacitance- and impedance- based transducers for high-sensitivity detection of acetone, toluene and TCE. Prototypes were embedded in filters in different locations, tested in a variety of conditions as specified in the NIOSH Filter Service Life test procedure, and successfully used for real-time tracking of the filter's internal concentration. The acetone detector met all of Honeywell's requirements for size, power, weight, sensitivity, and baseline characteristic. We also investigated polymer-nanocomposites for improving detection of toluene and trichloroethylene. One nanocomposite was successful for real-time tracking of both chemicals inside filters and demonstrated that it could be scaled to meet Honeywell's needs. These sensors still require optimization of sensitivity and power. Phase II will focus on readying the chemosensitive materials and transducers for transition either through sales or licensing to a filter manufacturer. Specific Phase II aims are to (1) optimize and complete the development of the acetone, toluene, and TCE detectors; (2) deliver working prototypes to Honeywell for validation testing in their filter-test labs; (3) support Honeywell's wireless readout circuit and sensor integration development; and (4) develop a manufacturing and transition plan to support commercialization. Honeywell tested Seacoast's prototypes and our Phase I results were shared with their team. Honeywell is eager to support our Phase II to create Smart Respirators for the over 544,000 workers in the US chemical manufacturing industries.