Google is telling its East Coast employees to stay home as wildfire smoke fills the air in New York and other major cities.

Company site leads in New York wrote in a memo to workers in the area that air quality in many parts of the region had reached “unhealthy” levels, citing the New York state Department of Environmental Conservation. In New York, most employees have been expected to work from physical offices at least three days a week.

“We are advising Googlers to work from home if possible, and limit their exposure to outdoor air,” according to the note, which was obtained by CNBC. “Terraces across our New York campus will remain closed today.”

According to NBC, the company issued advisory notices to workers in the Detroit area, Washington, D.C., Reston, Virginia, Pittsburgh and Raleigh-Durham, North Carolina. In Canada, which is on track to experience its worst-ever wildfire season, Google notified employees in the Ontario cities of Toronto and Waterloo.

New York Mayor Eric Adams issued a statement Wednesday urging all New Yorkers to limit outdoor activity, and airports delayed flights as smoke from Canadian wildfires engulfed surrounding regions.

Google has dealt with this issue in the recent past.

In 2020, the company’s home state of California faced hazardous air quality issues for almost a month as a result of record-setting wildfires that burned across the state. Many people at Google and across the tech industry were already working from home because it was the height of the Covid pandemic.

Google has set up a so-called “go” link that directs employees to internal documents and information about wildfires and air filtering. It released similar resources during the 2020 wildfires. The company typically has “go” links for things like products, employee equipment, office information and some social causes.

The memo on Wednesday advised employees to remain indoors, “avoid vigorous physical activity” and run their air conditioners with clean filters. The site leads assured those who are already working on site that the campuses’ HVAC and air filtration systems “maintain a high quality of air inside our offices even in these circumstances.”

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