The wildfires are again raging in the state of California. However, this time is different. This year’s fire season began in a perfect storm of smoke from the blazes, a scorching heatwave, and the ongoing COVID-19 pandemic. As expected, the Centers for Disease Control and Prevention (CDC) has come out with its guidance about how to prepare for wildfires.
In the guidelines posted on the government website, the CDC explicitly stated, “Cloth masks will not protect you from wildfire smoke.”
Cloth masks that are used to slow the spread of COVID-19 by blocking respiratory droplets offer little protection against wildfire smoke. They do not catch small, harmful particles in smoke that can harm your health.
Although N95 respirators do provide protection from wildfire smoke, they might be in short supply as frontline healthcare workers use them during the pandemic.
Unfortunately, the problem with the new CDC guidance is that smoke particles are far larger than COVID-19 droplets. According to information from the University of California San Francisco, wildfire smoke, and air pollution generally, are the microscopic particles that are about 2.5 microns in size (about 30 times smaller than the width of a human hair).
Traditionally, droplets are defined as large (>5 microns or 5μm) aqueous bodies. However, airborne nuclei (or aerosolized) transmission of the virus has been proposed as a source of infection almost since the inception of the COVID pandemic. Airborne droplet nuclei are less than 2.5 µm in size.
So if cloth masks cannot protect you from larger smoke particles, how can the same masks protect you from smaller COVID-19 droplets? This is not the first time CDC issued misleading guidelines. In the early days of coronavirus, the CDC intentionally lied to Americans about masks not being effective to prevent catching coronavirus but made the decision anyway not to wear one.
CDC also went on to social media to warn Americans that cloth masks will not protect them against the wildfire smoke. In a tweet from the official CDC account on Twitter, CDC said: “Wearing cloth masks in public can help stop the spread of #COVID19, but cloth masks won’t protect you from small particles in #wildfire smoke. Limit your time outside when it’s smoky. Learn more: https://bit.ly/3kSMjl9”
Wearing cloth masks in public can help stop the spread of #COVID19, but cloth masks won’t protect you from small particles in #wildfire smoke. Limit your time outside when it’s smoky. Learn more: https://t.co/jE1UsuXhtj pic.twitter.com/DvoCdZJkHV
— CDC Environment (@CDCEnvironment) September 10, 2020
