In December 2021, Boulder County in Colorado, USA experienced a devastating wildfire known as the Marshall Fire. Over 1,000 homes were destroyed, and thousands of acres of land were covered in smoke. The fire was fanned by winds reaching 115 MPH, spreading from south Boulder east to Superior and Louisville, ultimately claiming two lives and causing billions of dollars in property damage.

Images of the Boulder County wildfires in 2021/2022 — these fires were the most destructive in Colorado history, causing property damage and generating air pollution for surrounding communities.

In the aftermath of the fire, there were growing concerns about air quality and the safety of the residents returning to their homes and neighborhoods. To address these concerns, Boulder County Public Health deployed a network of Clarity Movement’s air quality sensors throughout the affected area, allowing the county to better understand and communicate the air quality conditions to residents. 

As Bill Hayes, Air Quality Coordinator at Boulder County Public Health, stated, "we had a lot of people very nervous, and we wanted to be able to provide them with information at the neighborhood level."

Before the fire, Boulder County's monitoring system consisted of three state-operated air monitoring stations that detected particulate matter and ozone levels. However, these stations were mostly upwind and outside the burn area, making them less effective in providing accurate air quality data for the affected communities.

Approximate burn area of the Marshall fire in red, with existing air monitoring stations marked in green.

With residents anxious to return to their homes after the fire, Boulder County Public Health needed to address their concerns about the safety of the air they were breathing, especially since many structures and materials had burned, releasing potentially toxic substances into the air.

The Challenge

The main challenge faced by Boulder County Public Health was to provide timely, accurate, and neighborhood-level air quality information to residents returning to their homes. 

As Hayes noted, "when they asked us, what am I breathing? Is it safe? We really didn't know." 

With concerns about toxins released into the air from the burnt structures, automobiles, and other materials, residents wanted to know if it was safe to return to their neighborhoods, take their children to school, or even be outside to play. Additionally, with the debris removal process underway, residents living close to these activities were worried about their exposure to poor air quality.

The Solution

To address this challenge, Boulder County Public Health collaborated with the city of Denver, which had an existing air monitoring system called Love My Air, which uses Clarity’s Node-S devices. In the days after the fire, Boulder County Public Health deployed six Clarity monitors that were repurposed from Denver. 

Clarity's air pollution monitoring equipment is solar-powered and cellular-connected, meaning Hayes and his team could rapidly deploy them to measure air quality in affected areas — even for remote sites without electrical infrastructure or WiFi connectivity.

Later, Bill’s team ordered additional monitors, bringing the total number of Clarity monitors in the burn area to 22. These Node-S devices, roughly the size of a loaf of bread and solar-powered, allowed for flexibility in placement and reliable data transmission via cellular networks.

"After the Marshall fire we installed a total of 22 monitors in the burn area. The Node-S is solar powered, has impressive battery-life and transmits data via cellular network. That means we could put these monitors anywhere that the sun shines and that you can make a cell call." 

— Bill Hayes, Air Quality Program Coordinator, Boulder County Public Health
A screenshot of Boulder County Public Health’s site and map for residents.
“I'm now able to see where each one of my monitors is. The color of the dot tells me what air quality it's currently recording. I can then click on any one of those individual monitors to get more information.”

— Bill Hayes, Air Quality Program Coordinator, Boulder County Public Health

The Outcome

With a total of 22 Clarity monitors installed throughout the 6,000-acre burn area, Boulder County Public Health provided real-time air quality data and ensured an adequate network of monitoring stations for neighborhood-level coverage. Alerts could be sent through the Love My Air platform to residents who opted in for text or email notifications, as well as displayed on the Boulder County Public Health website. This allowed Bill’s team to provide actionable information to concerned residents worried about the safety and air quality in their neighborhoods. In addition, the data collected by the Clarity monitors helped Boulder County Public Health make informed decisions on whether people should stay clear of certain areas based on the air quality data collected.

As Hayes explained, "there's no way that we could tell anyone that they were 100% safe, but this told us enough to know if we should be telling people to stay out of the area or not."

In addition, the success of using Clarity's portable air quality monitors during the Marshall Fire has led to the decision to redeploy these devices into other parts of the county, focusing on low-income neighborhoods, manufactured home communities, and areas with high ozone levels. As Hayes shared, "we're going to make sure that these areas aren't being disproportionately impacted with poor air quality."

By continuing to utilize Clarity’s air pollution sensors, Boulder County Public Health ensures that communities remain well informed about air quality in their neighborhoods, thus protecting their overall health and well-being.