Santa Barbara County APCD Is Quadrupling Its PurpleAir Network

by Amanda Hawkins July 13, 2026

Photo by Riccardo Tuninato on Unsplash

The Santa Barbara County Air Pollution Control District (APCD) is in the middle of one of the largest coordinated PurpleAir deployments a US air district has ever done. By the end of summer 2026, the district plans to have installed approximately 150 new PurpleAir sensors at schools, government buildings, and nonprofit organizations across the county, on top of the roughly 50 sensors it has been operating since 2018. When it's done, the district's community sensor network will be about four times its current size.

For anyone who has watched wildfire smoke settle into a Central Coast valley and wondered what the air was really doing three streets over, this program is a big deal.

What the District Announced

On September 10, 2025, APCD publicly opened enrollment for schools, nonprofits, and government agencies interested in hosting a district-owned PurpleAir sensor. The program is funded by two grants:

A December 2024 EPA Air Quality Sensors Grant under the Inflation Reduction Act, for roughly 40 sensors.
A June 2025 Memorandum of Understanding between APCD and the California Air Pollution Control Officers Association (CAPCOA), for about 100 more sensors funded by EPA passthrough dollars administered by CAPCOA.

Together, those two funding streams support the ~150 additional sensors being deployed across Santa Barbara County. According to APCD's September 2025 Community Advisory Council update, the district's priority is to install sensors "countywide in areas where there may be data gaps, especially in areas that are defined by the State of California as being disadvantaged and/or low-income."

That framing matters. Regulatory monitoring networks are expensive, so they tend to be concentrated where population, industry, or historical air quality problems concentrate. Community sensor networks like this one are how districts fill in the space in between, and prioritizing that infill in disadvantaged communities is a deliberate environmental justice choice.

Where the Data Lives

Every sensor installed under this program shows up in real time in two public places:

The PurpleAir map, where sensor names will include the tag SBCAPCD so anyone can identify district-hosted sensors at a glance.
The EPA AirNow Fire and Smoke Map, which applies EPA's correction factor for wildfire smoke and is the map most emergency managers, journalists, and school officials use during smoke events.

You do not need to be a resident of Santa Barbara County to see the data. Sensor readings are public, and anyone can zoom in on the county on either map.

Where the Sensors Fit in the Bigger Picture

The district's existing regulatory network is small but well placed. APCD operates five State and Local Air Monitoring Stations (SLAMS) at Lompoc, Santa Ynez, Santa Barbara, Santa Maria, and Goleta, plus seven Industrial stations sited near oil and gas operations. Those stations meet federal reference-method standards, and they are what the district uses for enforcement, State Implementation Plan reporting, and official Air Quality Index designations.

Twelve stations across a county the size of Santa Barbara (2,738 square miles) can only tell you so much. A community sensor network of 200 PurpleAir units, layered on top of those SLAMS stations, gives residents something the regulatory network is not designed to give them: neighborhood-level, minute-by-minute visibility into what the air is actually doing where they live, work, and send their kids to school.

APCD is careful about this distinction, and the program's Letter of Expectations says so explicitly:

Low-cost air quality sensors do not meet federal, state, or local regulatory requirements for air quality monitoring, air quality warnings, or enforcement. Therefore, APCD cannot use sensor data for any enforcement or regulatory purposes.

That is a feature, not a bug. Community sensors are for real-time community awareness. Regulatory monitors are for regulatory decisions. Having both, side by side, is how modern air districts increasingly want to operate.

Why Santa Barbara

Santa Barbara County has a long list of reasons to invest in neighborhood-level air monitoring:

Wildfire smoke. The Thomas, Cave, Alisal, and 2025 Lake fires all pushed heavy PM2.5 into county communities, sometimes for weeks. Smoke pools in the coastal valleys and behind the Santa Ynez range in ways that a handful of SLAMS stations cannot fully capture.
Agricultural dust and pesticide-adjacent communities. The Santa Maria and Lompoc valleys have large agricultural operations. Neighborhood-level PM sensors help residents in nearby communities see what they are breathing when fields are being worked.
Oil and gas operations. The Las Flores Canyon area and other operations produce localized emissions that industrial stations were built to measure, but community sensors extend visibility beyond fence lines.
Coastal-to-inland gradients. Air quality can differ dramatically between the coast, the foothills, and the interior valleys within a few miles. Community sensors are the only cost-effective way to see those gradients in real time.

Who Can Host a Sensor

APCD is soliciting sensor-host applications from schools, nonprofit organizations, and government agencies in Santa Barbara County. Host requirements are straightforward and are documented in the Letter of Expectations:

An outdoor-accessible 110V AC outlet within 15 feet of the mount
A stable Wi-Fi internet connection
A secure, accessible location approximately 5 or more feet off the ground
A commitment not to alter, modify, or tamper with the sensor

APCD lends the sensor to the host at no cost, and the data goes on the public maps. Interested organizations can fill out the online application form or contact the district directly at sensors@sbcapcd.org or (805) 979-8328.

The district has been clear that demand exceeds supply. In its January 2026 board outreach update, APCD staff noted that their first priority is schools, followed by government and nonprofit buildings, and that not every interested location will get a sensor. Applying early helps.

What This Means for the Rest of Us

Two things stand out here beyond Santa Barbara County itself.

First, this is what a mature government-and-community air monitoring partnership looks like. A district uses grant funding to lend hardware to schools, nonprofits, and other public buildings. The community hosts the sensors. The public sees the data on both the PurpleAir map and the EPA's Fire and Smoke Map. The regulatory network keeps doing its regulatory work, and the community network fills in the gaps. Everyone gets better information faster during smoke events, and the district gets a better view of neighborhood-level exposure inequities.

Second, the program is a proof point that low-cost sensors are now trusted enough by state and federal funders to be central to how districts respond to wildfire smoke. Between the EPA Inflation Reduction Act grant and the CAPCOA MOU, Santa Barbara APCD's expansion is being paid for by state and federal dollars specifically earmarked for this kind of deployment. Other California air districts, and increasingly districts outside California, are watching how it goes.

If you live in Santa Barbara County and know a school, church, community center, or local nonprofit that could host a sensor, this is the moment to point them at ourair.org/sensors. If you do not live in the county, you can still watch the network grow on the PurpleAir map and the AirNow Fire and Smoke Map. Search for sensors with SBCAPCD in the name to see the district's network.

Monitor your own neighborhood on the PurpleAir map, or bring a sensor home with an air quality monitor.