Abstract: A low energy particle detection device comprises alight source, multiple photodetectors positioned at different scattering angles, and a microcontroller for computing a total mass concentration of fine and ultrafine particles and a mass fraction of ultrafine particles to fine particles in an incoming air particle airflow based on the ratio of the readings from the multiple photodetectors. The optical particle detection device also can determine surface area concentration of the air particle sample and the associated lung deposited surface area (LDSA) to measure and improve estimates of air quality.

Abstract: A low energy particle detection device comprises alight source, multiple photodetectors positioned at different scattering angles, and a microcontroller for computing a total mass concentration of fine and ultrafine particles and a mass fraction of ultrafine particles to fine particles in an incoming air particle airflow based on the ratio of the readings from the multiple photodetectors. The optical particle detection device also can determine surface area concentration of the air particle sample and the associated lung deposited surface area (LDSA) to measure and improve estimates of air quality.

Abstract: Systems and method implement end-to-end capture of data fluents, the treating of said data locally, transmission of the data to a scalable server infrastructure, and retrieval and visualization of the data in a computationally efficient manner. Data is retrieved using a local electronic device that immediately time stamps data values and stores the values on a local buffer in order to compensate for any wireless signal vagaries. Local wireless configuration of the device consists of wireless-based configuration interactive menus, enabling high ease- of-use during setup and administration. Data is then communicated during times of Internet connectivity to an online data storage repository.

Abstract: Computer-based systems and methods characterize indoor air quality in a particular building having multiple locations therein. The system comprises a back-end data center, at least one indoor air quality sensor located inside the particular building, and a graphical display device. The indoor air quality sensor(s) transmits time-stamped air quality readings collected by it to the data center via a computer network. The data center computes spatiotemporal air quality measures for the particular building based on the time-stamped air quality readings from the indoor air quality sensor(s) and transmits the computed spatiotemporal air quality measures to the graphical display device for display to the user/resident.

Abstract: Systems and methods batch calibrate environmental sensors. Candidate environmental sensors and a high-performance reference sensor are located in an enclosure with a particle excitation system that controls the particle concentration in the enclosure. The calibration process includes multiple phases with different particle concentrations, and the candidate and reference sensors continuously report their particle counts to a calibration server during these phases. Based on the collected data, the calibration server: (i) identifies for removal candidate sensors with outlying behavior through statistical analysis; and (ii) computes calibration values for the particle count estimation algorithms for the remaining candidate sensors that are optimized to minimize the error relative to the reference sensor(s).

Abstract: Air quality sensor comprises an optical particle sensor and a programmable processor circuit. The optical particle sensor detects particles having a size of 10 microns or less in diameter in ambient air of the optical particle sensor. The programmable processor circuit continuously computes updated air quality measures for the ambient air using an estimation algorithm based on pulses in an output signal from the particle sensor over time, such as a cumulative particle density value and/or a cumulative particle weight value. The optical particle sensor may comprise a LED and accordingly detect particles based on reflection of light energy from the LED by particles in a chamber of the sensor.