Particle Sensing is the act of detecting dust in the air, and characterizing that dust and its potential health effects on those who may breathe it. There are four major factors necessary to determining what particles are in the air and addressing the source, particle concentration, particle size, particle type, and particle source. Different particle sensing strategies are useful in determining these factors.

Particle Concentration

Particle concentration is the density of particles in the air. This is usually expressed as micrograms per cubic meter, or μg/m3.

Particle Size

Particles are measured in micrometers (μm), and sometimes in the shorthand such as 'PM10' meaning, particulate matter roughly 10μm in diameter. PM1, PM2.5, PM5, PM10, and PM15 are frequently seen measurements of particle size, and regulations will often be expressed in these terms.

Particle Type

This can be conducted with a microscope for crystals, and using lab techniques for other types of particles.

Particle Source

Usually directional and time-stamped data from multiple points are needed to extrapolate source, along with an understanding of particle type.

Particles of Concern

There are a lot of problematic dust particles. Silica is currently a Public Lab monitoring project. Add more here

Strategies and Sensors

Electronic sensors

Most electronic sensors are essentially a light that gets interrupted by a particle, with a camera or other optical sensor watching. The Speck uses a Syhitech DSM501A The Dustduino Uses a Shenyei PPD42NS

Sticky Pads

Essentially tape, sticky pads have the advantage of capturing a record of actual particles that can be analyzed later. They can be scanned and digitized for standardized readings. More can be found on the Sustainable Aggregates website.