Continuous PM2.5 Monitoring Washington State

Continuous PM2.5 Monitoring Devices used in Washington Nephelometers Tapered Element Oscillating Microbalances (TEOM) Beta Attenuation Monitors (BAM) Aethalometers

Continuous PM2.5 Monitoring Nephelometers are in the majority (50) TEOM’s (15) & BAM’s (4) are next Aethalometers are typically collocated with another continuous device (10 )

Continuous PM2.5 Monitoring Why nephelometers? Dependable & reliable Easy to operate Function well in all parts of the state Correlate well with FRM Currently cost effective VS other devices

Continuous PM2.5 Monitoring Why nephelometers? Cont. Provide geographic representation for public health AQI

Continuous PM2.5 Monitoring Any down side to nephelometers? Acquisition of parts & service from the current vendor can be time consuming Not an equivalent method – current vendor may never be

Continuous PM2.5 Monitoring The future of nephelometers in Washington: Short term - press on, business as usual Long term - serviceability questions and potential problems with equivalency

Continuous PM2.5 Monitoring Planned future work: Look at other continuous monitoring options, new vendors Model confirmation – returning to locations to run short term and seasonal correlation verification Develop models outside of the current, year-round look Automation of zero & spans to reduce operator trips to remote sites