Technology

Water tender crews monitor a backfire during the Mosquito fire in Foresthill, an unincorporated area of Placer County, California on September 13, 2022.
Josh Edelson | AFP | Getty Images

As a massive wildfire chewed through tens of thousands of acres in California over the past week, smoke and ash billowed into nearby towns including Sparks — home to Tesla’s Gigafactory in Nevada.

Tesla is taking steps to shield employees from exposure to the smoke from the wildfire — known as the Mosquito Fire — as much as possible but the company stopped shy of furloughing workers.

According to an internal memo shared with CNBC, Tesla informed employees at the facility that the building’s heating, venting and cooling (HVAC) system was set to a “recirculation mode to limit the amount of outside air pulled into the factory.”

Overall air quality around the Tesla facility was ranked “unhealthy” to “very unhealthy” on Thursday and Friday with around 57 micrograms of fine particulate matter per cubic meter of air, according to the U.S. Air Quality Index.

When air quality is that poor, people of all ages are advised to seriously limit outdoor activities, and wear a mask outside to filter smoke and other pollutants. They are also advised to keep windows closed to shut the pollution out of their homes and offices.

Nevada Gigafactory HVAC filters have been upgraded to a MERV 13 level or higher over the past year to capture wildfire particulates. Those filters have been swapped out for new ones on a more frequent basis this year, Tesla told workers, and that should continue amid the smoky conditions.

The region was plagued with wildfires and air pollution last year as well. California’s Caldor Fire, for example, burned more than 220,000 acres in 2021, destroying homes, land and leading to hazardous air quality in surrounding areas including in Nevada.

According to the California Air Resources Board (CARB), “climate change, primarily caused by the burning of fossil fuels, is increasing the frequency and severity of wildfires not only in California but also all over the world.”

Workers stationed at or frequently going to outdoor areas were urged to pick up N95 masks at an office in the Gigafactory, and kept apprised of air quality levels this week as well.

The Mosquito Fire was 20% contained as of late Friday according to the CalFire website, with cooler weather forecast over the weekend that was expected to aid fire fighters in their effort to extinguish the flames.