SBIR-STTR Award

The aim of the proposed work is to develop a low-cost micro analyzer for monitoring workplace exposures to a specific, and acutely toxic, gas, namely hydrogen sulfide. Recent work by Nanomaterials Research Corporation has shown that a new semiconductor compound is highly responsive to low gas concentrations when held near ambient temperature. This unique discovery provides the opportunity for improved discrimination between gas species (a problem with existing metal oxide sensors, which alarm in the presence of other compounds) . -Furthermore, the device should operate at very low power, making it suitable for battery-powered personal exposure monitors. Finally, the interaction between the sensor and the gas is rapidly reversible, enabling continuous monitoring and the acquisition of cumulative exposure data. PROPOSED COMMERCIAL APPLICATION: Hydrogen sulfide is an extremely toxic gas, and exposure to even low concentrations can lead to respiratory system paralysis, fainting, and even death. It occurs in large amounts in natural gas and petroleum and is a common byproduct of many industrial processes. OSHA reports more than 70 occupations where workers are routinely exposed to this gas, many of which involve entering confined spaces where concentrations are often high. Personal exposure monitors can supplement existing technology, providing an added measure of worker safety in these instances.

Nanomaterials Research's primary objective for this SBIR project is the design, development, and demonstration of a better sensor technology for the detection of hydrogen sulfide Hydrogen sulfide is a colorless, flammable gas that is highly toxic It reacts with the enzymes in the blood that inhibit cell respiration At high concentrations, it can literally shut off the lungs, while lower levels can burn the respiratory tract and cause eye irritation This gas is encountered in a wide range of industries, and a number of standards have been established for occupational exposure The OSHA Permissible Exposure Limit (PEL) is 10 ppm, the Short Term Exposure Limit (STEL) is 15 ppm, and exposures of 300 ppm or greater are considered immediately dangerous to life and health (IDLH) Because of the potential for adverse health effects at low concentrations, the industrial hygiene community is continually seeking improved performance from hydrogen sulfide sensors Specific requirements include reliable and accurate detection in real time, quantitative measurement capabilities, low purchase and life cycle costs, and low power consumption (for portability) Sensors meeting these requirements will find numerous applications within the health and safety field In addition, there are several potential spin-off opportunities in leak detection, emission monitoring, and process control Nanomaterials' approach is to utilize alternative ceramic oxide materials, and a unique multilayer fabrication process to accomplish the objectives of this project The work plan includes optimization of the sensor materials, sensor element fabrication, sensor element packaging, in-house and external evaluation of the sensors, and establishing the foundation for new instrument development The ultimate aim is a low-cost, low-power sensor that can be used in a new type of personal monitor The envisioned monitor is a low profile, credit card sized "smart-card" that can not only alert the wearer when unsafe concentrations have been encountered but also to track cumulative individual worker exposure to a particular toxic gas species.

Public Health Relevance:
This Public Health Relevance is not available.

Thesaurus Terms:
Air Sampling /Monitoring, Biomedical Equipment Development, Gas Analyzer, Hydrogen Sulfide, Monitoring Device, Occupational Health /Safety, Portable Biomedical Equipment Biomaterial Development /Preparation, Ceramic, Miniature Biomedical Equipment, Nonbiomedical Equipment, Oxide Bioengineering /Biomedical Engineering