Skip Navigation


Export to Word (
Principal Investigator: Hering, Susanne Vera
Institute Receiving Award Aerosol Dynamics, Inc.
Location Berkeley, CA
Grant Number R44ES031458
Funding Organization National Institute of Environmental Health Sciences
Award Funding Period 01 Apr 2020 to 31 Mar 2025
DESCRIPTION (provided by applicant): A PULSED CONDENSATION PARTICLE COUNTER FOR COST EFFECTIVE MONITORING OF ULTRAFINE AIRBORNE PARTICLES ABSTRACT This project will develop and validate a new approach for affordably monitoring the number concentration of ultrafine airborne particles. Ultrafine particles are specifically implicated in health, and yet are not detected by lower-cost sensors. Our approach is a Pulsed Condensation Particle Counter that uses adiabatic expansion combined with single particle counting. Our Phase I results demonstrate that this approach is reliable over months of continuous operation, with ±10% agreement with expensive, research-grade condensation particle counters. Our target is an affordable portable instrument, priced at a fraction of the cost of current instruments, that measures the particle number concentration with known accuracy and precision. The envisioned commercial instrument will include a commercial optical counter and report ultrafine particle number concentration and estimated PM2.5 mass. This Phase II project will improve the performance of the Phase I system, refine the supporting components, and integrate the electronics and components into a compact system. The complete prototype system will be tested under both laboratory and field conditions. Instrument precision and accuracy over a range of particle sizes and concentrations will be evaluated with monodispersed, laboratory aerosols, using particle sizes ranging from 5 nm to 2500 nm, and concentrations from near zero to several hundred thousand per cubic centimeter. Instrument robustness will be evaluated through stress-testing at extremes in temperature (5°- 40°C) and humidity (5%-95%). Monitoring performance and stability will be tested through comparison with collocated benchtop instruments over weeks of unattended operation. Measurements under field conditions will be conducted in collaboration with a local university exposure study. Validation as a monitor will be done in collaboration with an air monitoring district. The objective is a compact, cost-effective monitor with a particle detection limit below 5 nm, with precision of ±10% for concentrations between 10 - 104/cm3, and precision of at least ±15% for concentrations reaching 105/cm3, and data recovery of at least 90%.
Science Code(s)/Area of Science(s) Primary: 74 - Biosensors/Biomarkers
Secondary: 03 - Carcinogenesis/Cell Transformation
Publications No publications associated with this grant
Program Officer Lingamanaidu Ravichandran
to Top