Mobile sensors for NOx und PM (particulate matter)


  1. Is it possible to combine these 2 types of sensors to monitor NOx and PM? Or is it necessary to have them separated into one housing? We want to install mobile sensors.
  2. Are there any restrictions if we build them together (NOx and PM sensors) into one housing?
  3. How can we estimate the number of mobile sensors we will need?


  1. Possible to combine?

I don’t see why you couldn’t combine both types of sensors into a single device. The key idea is to allow sufficient access to the air for each sensor.

  1. Restrictions if together in one housing?

The only restrictions I can imagine would be that you have to design the housing in such a way that they both get good access to the air they are intended to measure. This is a mechanical, fluids, and thermodynamics design problem which should be solvable through modeling and/or experimentation. In general, the larger you make the housing, the easier it should be to arrange the two sensors in a way that they do not interfere with each other.

  1. Estimate number of sensors needed?

The answer is completely application dependent. It would depend on the size of the area to be “sensed”, how much air movement/mixing there is within that area, and how much resolution you need within that area.