The Need

There is a critical need for a reliable, cost-effective, and safe method to detect gas leaks, particularly in gas lines to ensure the safety of service providers and customers. Distribution companies receive over 100,000 calls per year responding to gas odors, indicating potential leaks. The majority of their requests to monitor gas odors are residential calls. Several methane detection technologies are available that enable responders to detect gas leaks, and the most common system is based on flame ionization detection. This handheld technology is inexpensive and reliable, but it requires direct contact with the methane gas, putting the operator at risk. Optical technologies, such as passive imaging or active tunable diode laser spectroscopy, enable stand-off detection of leaks. However, their detection reliability and acquisition costs are problematic. Thus, there is a need to develop a stand-off detection technology to assess methane risk from a safe distance to locate the leak source.

The Technology

Researchers at The Ohio State University, led by Dr. Sanjay Krishna, have developed a stand-off methane detection system with active, laser-based sensing and imaging capabilities that exceeds the current state-of-the-art. This new technology can detect methane outside of a building at a safe standoff distance and at explosive level concentrations (4-15% by volume). The lasers will actively illuminate a scene, and a processor modulates the light source between an on-resonance state and an off-resonance state, relative to the absorption spectrum of the target gas. By tuning the lasers, the device exploits spectroscopic absorption features at specific wavelengths in the infrared to detect relevant gasses. Imaging provides several advantages, including potential localization of leak sources and characterization of the spatial extent of gas clouds. In addition, the image of the cloud enables more accurate quanitifcation of teh gas concentration, exceeding the capability of commercial systems that only provide a concentration-path length (CL) product instead of a pure concentration. Finally, the infrared wavelengths have been selected such that the laser beams can propagate through typical commercial window glass, thereby enabling through-window sensing of the interior of a building. This system is easy to use, portable, reliable, and cost-effective.

Commercial Applications

• Gas Distribution Companies and Utilities: Quick and reliable detection of gas leaks.
• First Responders: Safe detection of gas leaks from a distance.
• Industrial Safety: Monitoring of potential gas leaks in industrial environments.

Benefits/Advantages

• Safety: The technology operates from a safe distance, reducing risk to operators.
• Reliability: The technology provides reliable detection of target gases.
• Ease of Use: The technology is designed to be user-friendly, requiring minimal training.
• Cost-Effective: The technology is designed to be cost-effective with infrequent and inexpensive maintenance.