Particle Physics and Particle Counting for IH&S and IAQ Thomas J. Grillo, Jr. Particles Plus, Inc.

Overview Particle Behavior Particle counters & what are we detecting Types of Particle Counters Typical Features and Operation Q & A

Particles and their behavior Particles come in all different types, shapes and sizes. A human hair is 80-100 µm in size The human eye can see 40 micron size particles Particle size effects their behavior Gravity vs. Brownian Motion Effect Settling rate influenced by size, shape, and density. Particles relative to Indoor Air Quality & IH&S Particles can deposit in human lungs Particles affect human health size and shape affect IAQ performance

Particles and their behavior Brownian Motion Smaller particles and atoms influence larger particles’ direction and speed of motion in a liquid or gas Gravity Particles > 5.0 µm – falling debris Partilcles < 5.0 µm – tendency to remain airborne - suspension Aerodynamic shape and density play a role Environmental influences Airflow/Ventilation/Occupancy

Air Quality Monitoring

What is a Particle Counter – How it works A particle counter is an instrument or sensor that detects and counts physical particles. The nature of particle counting is based upon either light scattering, light obscuration, or direct imaging. A high intensity light source (typically a laser) is used to illuminate particles as they pass through the detection chamber. As a particle passes through the light source and if light scattering is used, then the redirected light is detected by a photo detector. (Wikipedia)

Why use a particle counter? Detect Monitor Analyze Remediate and Prevent

Why use a particle counter? To provide a quantitative analysis of airborne particulate for quality control regulatory requirements for public health and safety limiting liability Monitoring for employee (or occupant) health and safety Air Quality Analysis for resolving & remediating

Types - Air Quality Monitors Used to monitor in fixed location for long term analysis Includes Particulate, Temp, RH, CO2 & TVOC

Types - Handheld Particle Counters Mobility – Ideal for site investigation Establish a baseline for airborne particulate levels. Post remediation checks before clearance testing.

Types - Remote Particle Counters Wall mount versions for fixed construction barrier applications Long term onsite analysis for PM or direct counts

Types – Dust Monitors Most prevalent in IH&S applications for mass concentration measurments Limited by mechanical impactors or cyclones

Types – Gravimetric Sampling Fixed flow pumps with impactors or cyclones utilizing pre-weighed filter media that can collect a sample over time and the weight can be rechecked by a lab for a value in mass concentration (µg/m³) Can also be evaluated by Microscopy for quantitative and qualitative analysis.

Types – other technologies – R&D Differential Mobility Analyzers CPC - Condensate Particle Counter Piezo Balance – Wetted particles CPC – Quantitative only Beta Ray Attenuation – continuous outdoor monitoring

Air Quality Monitoring Using a Particle Counter Air Quality Monitoring

User Interface – Main Screen The instrument calculates Count/M³ based on the Flow rate of the instrument and the duration of the sample 0.3 = 583,392 0.5 = 50,976 1.0 = 25,134 2.5 = 6,726 5.0 = 1,770 10.0 = 354 Displaying Raw Counts in both cumulative and differential counts

Understanding ISO 14644-1 Particle Counts

User Interface – Main Screen

User Interface – Air Quality Monitoring

User Interface – Geiger, Beep or Real-time Meter Modes Provides a auditory (or visual and auditory) means of displaying current particle count activity that can be used to help locate particulate sources (shown with range slider to adjust sensitivity)

Sampling and Logging Log individual data records Locations and recipes Newer features like annotations and on screen statistics

Processing Power More advanced with multiple microprocessors onboard Allows for simultaneous processing of particle counts, accessing settings, viewing saved records, downloading data, and supporting many communications sessions. Concurrent Communications interfaces include: Multiple Modbus sessions (wired and WiFi) Multiple web-server sessions (wired and WiFi) USB data-download and configuration USB printer or thumb-drive

Intelligent Peripherals Swappable peripherals allow more flexibility for each instrument – other environmental or air flow related. Allows instrumentation to be configured for the task-at-hand (IAQ, H&S, QC, Certification & Validation) Allows instruments to expand over time to add new features – handheld probes, etc.

Instrument Management Software Real-time graph allows for instrument operation and control Saves data for historical review, reporting and analysis

Instrument Management Software Self-calibration of TVOC, CO2, Temperature and Humidity sensors Allows for remote service and upgrades

Q&A Thank You! www.particlesplus.com