Air quality sensing
Air pollution is an ever more growing health and environmental problem in cities, affecting both the population of the city and neighbouring regions. According to the World Health Organization is air pollution the largest environmental risk factor causing an estimated 7 million deaths (1 out of 8 people who died) during 2012. Real-time air pollution monitoring is an absolutely necessary tool for the public to be informed and for the authorities to able to take appropriate and decisive actions to counter this serious threat. Traditionally, air pollution is monitored by expensive, stationary, and complex instrumentation. Therefore, the grid-resolution of measurements is poor. In Mumbai, for example, a city of some 4400 km2 with a population greater than 20 million, the local state pollution control board is served by only three measurement stations. This makes it difficult to assess local variations in air quality, to pinpoint the source of pollution, and for decision makers to take fast action in response to local air pollution episodes, e.g. real-time traffic congestion control.
New, low-cost, miniaturized, and energy efficient sensors that can be integrated in measurement devices placed in numerous locations throughout urban areas, placed in vehicles, or carried around by individuals, has the potential to completely change the way air quality data is collected and analysed. Such sensors can for example be used to empower the public with unbiased real-time information, to acquire spatiotemporal pollution data aiding in urban planning and traffic control, and to regulate outdoor-indoor air exchange in buildings and cars.
Insplorion’s proprietary NPS technology is very well suited for employment in portable low-cost air quality monitoring devices. Advantages compared to existing gas sensing technology include:
- Can be miniaturized such that a sensor with multiplexing function does not increase in size compared to a sensor with single sensing capability.
- Self-calibrating with an integrated reference.
- Transducer element does not draw any power. Multiplexing can be implemented by employing multiple transducer elements without increasing the overall energy consumption of the device.
- Extremely fast response/restore times due to surface sensitivity of NPS.
- Detection limit can be engineered to give a very large dynamic range