The device does not have a range.

if you barbecue in your backyard for example you can have a spike that is ultra local. PM results typically double from sidewalk to the center of a busy street. The result you get in terms of range will depend on distance to sources, diffusion rate, bulk transport and long range average. As a result, an instantaneous reading will probably reflect your immediate local environment, while a daily average will reflect the weighted average of a large range upwind. for example, let say there is a constant south wind at 1mile/h, PM diffusion rate 0.1mile/h, and the long range PM value is 5ug/m3. your 1h average PM reading area will look at the long range value plus sources in a 1milex0.2mile ellipse due south. your 24h reading will look at 24milesx4.8miles area + long range PM. The weight of the area in term of range will be proportional to the distance: local sources will weight more than far away sources. Evidently, wind direction and diffusion rate will greatly change based on a lot of factors, and you need powerful atmospheric models to account for that. You will also need a correct model to know where the sources are.

The value of the device is in its ultra local result and in the grid