1. EPA’s Next Generation Air Monitoring Workshop Series Air Sensors 2013: Data Quality & Applications EPA RTP, NC March 19 & 20, 2013 EPA’s Village Green Project Gayle Hagler and Ron Williams VGP co-leads 1

2. Motivation 2 Concentrations of certain air pollutants varies with time and location at a local level e.g., Zhu et al (2002)  In order to resolve local concentration trends in neighborhoods near sources, lower-cost measurement systems sensitive at ambient concentrations would be helpful

3. Stationary, active air monitoring technology Emerging tiers of technology Tier 1: Regulatory or regulatory-equivalent air monitoring stations Cost: 100s (in thousands), Data reliability = A+ Tier 2: Smaller-footprint monitoring systems for communities and research studies Cost: 1-10s, Data reliability = B+ (target) Tier 3: Very small, very low cost systems enabling dense sensor networks, citizen science Cost: 0.1-1s, Data reliability = ? *Image source: http://portrichmondair.org existing emerging

4. Designing the VGP system Tier 2: Smaller-footprint monitoring systems for communities and research studies Cost: 1-10s, Data reliability = B+ (target) Data Public Outreach Sustainability self-powered low maintenance lower cost direct readings (no labwork) relevant air quality indicators supporting data (meteorology) adds value to location fun and interactive educational

5. Components – power Power and space are the key drivers in our design Power system: 2 solar panels (80 Watts) Battery module Power drop recovery – Instruments will have controlled shut-down if battery drops to a low level, restart automatically when available power increases.

6. Components – air monitor Fine particles (top left) and black carbon (will be in top right spot) instruments 6 Ozone instrument Instruments incorporated are commercially available and provide direct, real-time readings (seconds to minutes) as well as diagnostic indicators Wind, temperature, relative humidity

7. Components – communications Cell modem Arduino ADK microprocessor + shields supporting data in/out communication, control of power module System communications and controls:

8. Components – structure Structure design: Draft designs of potential VGP systems - Sustainable materials: manufactured from recycled milk jugs - Tamper-proof: Instruments secured in bench or base of play structure - Designed to add value to public environments (playground structure, bench)

9. Data transmission and checks Instrument Measurements (ancillary in italics) Microaethalometer (AethLabs) Black carbon Light attenuation Ozone Monitor on a Board (Model OEM-106, 2B Technologies) Ozone Cell pressure Flow rate Temperature Pressure Diode voltage Particulate Monitor (MIE pDR- 1500, Thermo Scientific) PM 2.5 Pressure Humidity Temperature Weather sensors (wind speed and direction; thermocouple; RH sensor) 2D wind speed 2D wind direction Ambient temperature Ambient relative humidity Arduino ADK microprocessorStatus (e.g., 4 = instruments on) - Data transmitted via cellular modem to HTTP server - Data screened on SQL server for various diagnostic indicators, averaged to desired interval (e.g., 5 min, hourly, daily) - Data available to web browser interface

10. Website interface (draft) Ability to explore recent measurements, graph in different time intervals

11. Website interface (draft) Ability to observe how system is performing while running on solar power (e.g., winter- time sampling in North Carolina)

12. Next steps Design and build system and website infrastructure – “proof of concept” System is running, reporting data to website with appropriate QA checks/caveats We are here… We’re hoping to be here in May Moving parts: - Migration of beta-testing site and server to be on EPA’s infrastructure - Encase air monitor and power system into bench structure (under construction) - Trial test of integrated system - Install station to pilot at community location for 2012-2013 - Communicate frequently through blogs

13. Pilot-testing at Durham Public Library Bench-style monitor will be located on library property. May be part of outreach activities with Lowes Grove Middle School, located across the street. South North Solar panels at 55 degree angle

14. Critical to success - interdisciplinary team! Interdisciplinary Team: Gayle Hagler – Project co-lead, NRMRL Ron Williams – Project co-lead, NERL Eben Thoma - NRMRL Bill Mitchell - NRMRL Kelly Leovic – EPA-RTP Outreach program, NERL Rachel Clark – EPA-RTP Outreach program Vasu Kilaru – Innovation Team / NERL Emily Snyder – Innovation Team / NHSRC John Masters – Web and communications Katie Lubinsky – Communications Dana Buchbinder – Communications EPA National Computing Center EPA Office of Science Information Management ARCADIS – VGP system and database fabrication