For environmental monitoring, air quality and climate research, regulations are becoming more strict to reduce the hazardous effects of the air pollutantst. Due to their high sensitivity and selectivity, low cost of ownership, no need for frequent calibration, virtual maintenance free and operation without being on site, the optical techniques are the most suiitable ones for environmental monitoring. Sensor Sense has developed several gas detectors that are currently used in field measurements.
The ETD-300 ethylene detector is suitable for use inside aircraft, being extremely stable in harsh conditions (i.e. excessive vibrations, temperature changes and pressure variations). These unique characteristics were fully exploited during the Texas Air Quality Study (TexAQS II) in 2006 together with NOAA Chemical Sciences Division, Boulder, Colorado in monitoring ethylene emission from industrial sources near Houston. Ethylene is of particular interest since it plays a role in ozone chemistry in the atmosphere.
Ethylene emission from various sources (blue triangles) measured with ETD-300.
Ammonia plays an important role in acidification and eutrophication. In the natural atmosphere ammonia concentrations can be very low, therefore, our inexpensive and very accurate ammonia detector with a detection limit of 1 ppbv or lower are an excellent tool. In intensive farming areas, ammonia concentrations can reach ppmv levels. Monitoring ambient ammonia levels for environmental analysis does not demand for extremely fast detectors. A minute time response is considered sifficient when measuring in the controlled venting system in stables.
Nitrous oxide is a major greenhouse gas with a very high global warming potential. It is emitted from the soil and emission increases with N inputs. Nitrous oxide is an air pollutant that causes ozone depletion. It also has to be monitored in stacks from industry, agricultural sources need to be studied as well. LSE Monitors, a joint venture between Sensor Sense and Synspec, has developed a low price, small and effective N2O detector to measure from ppm to mid ppb range, with a detection limit of 10 ppb and a time resolution of 90 seconds.