Using the Smoke Sense App During the Camp Fire in California

By Wayne E. Cascio, MD, FACC

On Nov. 8, 2018, at 6:33 am the Camp Fire erupted with a fury in Butte County near the town of Paradise. This rolling inferno turned a small, quiet community to ashes, leaving little more than memories behind. Even those of us who were not present have a new understanding of the destruction of wildfires — stories from survivors and images of the scorched cars that carried people to safety through the flames have been shared all around the world. And we are all thankful for the heroism of the firefighters and fire managers who put it all on the line to save lives.

The images from NASA’s satellites tell another story, of massive amounts of particle and gas emissions rising into the atmosphere, eventually impacting San Francisco, Oakland, San Jose, and many other cities and towns with wildfire smoke. Coincidentally, I was in Sacramento to give a presentation on EPA’s wildfire research at the Society of Environmental Toxicology and Chemistry (SETAC), along with many of my EPA colleagues, when I learned of the tragedy of Paradise. I discovered firsthand how smoke originating from a wildfire, even one almost one hundred miles away, can affect the lives of those near and far from the fire.

In only a few days, millions of Californians were under a blanket of smoke that affected visibility and, for some, their health, and EPA’s public health information, including the Smoke Sense app, was there to help. In the first two days of the fire, air quality in Sacramento was mildly impacted, causing a haziness and an acrid smell of smoke. During casual conversations with people on the street, a comment about the smoke would invariably be made and I would demonstrate the Smoke Sense app on my mobile phone. Just about everyone who saw Smoke Sense wanted to download it.

SmokeSense IconThe Smoke Sense app was developed as a citizen science project by one of our scientists, Ana Rappold, and her team in EPA’s Office of Research and Development. Nearly 20,000 people are now using the app to learn about air quality. I’ve been a strong advocate of Smoke Sense and I’ve demonstrated the app just about everywhere – on the street, in hotel lobbies, in a jet taxiing to the gate, and even in an elevator. Yet, I’d never had an occasion to use the app to convey real-time, important information.

In Sacramento and San Francisco, Smoke Sense provided useful information about local air quality, actions I should take to limit my exposure, and where the smoke was located as well as what was anticipated for the next day. Many people were curious about the app and were amazed that it provided so much useful information.

While I was in San Francisco, air quality deteriorated further, and I estimate only about one of 15 people who were outdoors were making some effort to reduce exposure to smoke. People were using bandannas, paper painter’s masks, and surgical masks, but those do not offer much protection. However, I did see some N-95 respirators in use, which EPA recommends during smoke events when being outdoors is unavoidable.

Individual and non-profit organizations were stepping up to provide N-95 respirators to those in need throughout the area. In fact, I witnessed one group on Market Street distributing N-95 masks to all who would take them. Some people wore them correctly, but for others, the masks fit poorly or weren’t doing much good hanging around their necks. One older man who was walking slowly assisted by his cane and wearing a blue paper painter’s mask eagerly downloaded the Smoke Sense app and immediately began to explore the map showing where smoke was present. We later learned he is 84 years old and has heart disease. Two days later we saw him with an N-95 respirator making his rounds in the neighborhood. If he needed to be outdoors the use of the proper mask should offer some protection. Success!

Not all of those I spoke to were open to the idea of protecting themselves from the smoke. While on a trolley, a man riding with us across town asked why we were wearing masks. He acknowledged that smoke might be a problem for someone with asthma, but otherwise was not concerned. It showed me the great need to educate people about the potential health impacts of smoke from wildfires.

As the origins and consequences of the Camp Fire are investigated and studied, I trust that lessons learned can be used to prevent future wildfires and the tragic loss of life and property. In the meantime, Smoke Sense is doing its small part to help.

About the author: Wayne Cascio is the director of the National Health and Environmental Effects Research Laboratory, U.S. EPA.

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