The HPMA115SO-XXX from Honeywell is a HPM series PM2.5 particle sensor with UART output. The HPM series particle sensor is a laser based sensor which uses light scattering method to detect and count particles in concentration range of 0µg/m3 to 1000µg/m3 in a given environment. A laser light source illuminates particle as it is pulled through the detection chamber. As particles pass through the laser beam, the light source becomes obscured and is recorded on the photo or light detector. The light is then analysed and converted to an electrical signal providing particulate size and quantity to calculate concentrations in real time. The Honeywell particle sensor provides information on the particle concentration for given particle concentration range. It is used in potential industrial applications such as HVAC (air conditioners, air quality monitors, environmental monitoring) and consumer products (air cleaners, conditioners, purifiers, car air cleaners, handheld air quality detectors).