Of smoke and masks; how do we wear masks now and what works for smoke?

The Mono County Health Department
Special to the Times

According to local officials who work with the Great Basin Unified Air Pollution Control District, the Creek Fire smoke will likely be with Mammoth and the Eastern Sierra at least through this week and into next week - and perhaps longer than that.

Although the smoke might get a bit less dense due to an incoming cold front and stronger winds this week, if the fire continues to grow and the winds continue to come from a south or southwest direction as is forecast for quite some time, the Mammoth area and northern Mono County in particular, will likely be in for quite a bit more smoke, possibly into the end of the month. The most likely way the smoke will end completely is via a good, winter-like storm, which is not in the forecast at this time, said Tom Schaniel Air Pollution Control Officer with Great Basin.

Until then, he said, the smoke could get lighter, it could shift into valleys overnight and shift to more upslope areas in the afternoon with inversion patterns, but some, or a lot of it, will still be in the area until a large, seasonal storm or wind event scours the smoke out of the region.

That means locals need to learn to live with the smoke, right in the middle of a pandemic; a pandemic that scientists have determined is best controlled by wearing masks. But what works on smoke?

The Times received the below information from the Mono County Health Department recently regarding how to deal with smoke and masks:

How do residents know if the smoke outside is a health threat?
“You can tell when there is smoke in the area, but the intensity and concentration of the smoke is key, and it changes constantly with wind and weather,” the Mono County Public Health department said. “People react differently to smoke exposure - some people are more sensitive than others. Wildfire smoke contains a lot of stuff: gases and particles, depending on what is burning and how far away the fire is from your home. From a community health perspective, very small airborne particles (particulate pollution) are most important. Small particles are inhaled deep into the lungs where they may cause inflammation. Particle pollution also often causes local irritation of the eyes and throat.”

How is the smoke in the air measured?
Great Basin Unified Air Pollution Control District, based in Bishop, continually monitors air quality in numerous locations in Mono and Inyo and County and posts air quality data on their website in real time (see below for the link to the district), according to the health department.

“GBUAPCD posts particle pollution measurements, often in two categories of particle size. The smallest particles, less than 2.5 microns, are reported as PM2.5, which is considered the best measurement of wildfire smoke concentration.

“The concentration of particles less than 10 micrometers (PM10) is also a valid indicator of wildfire smoke pollution,” they said. “Locally, when either PM2.5 or PM10 levels exceed 100, a Stage 1 Health Advisory is issued, a recommendation that vulnerable people avoid strenuous outdoor activity.

“When particle concentrations are over 200, as has occurred many of the days since the Creek Fire started sending smoke into the area, a Stage 2 Health Advisory is issued, recommending that everyone avoid strenuous outdoor activity and that vulnerable people stay indoors,” the health department said.

When either of these occur, the air pollution district will send out emails to people, media and agencies.

“The Mono County Health department will share communications about Stage 2 advisories with those on our Monogram distribution list, but you can sign up on the GBUAPCD website to receive alerts directly (https://www.gbuapcd.org),” they said.

What are the long-term effects of this much exposure to smoke?
Whether on-and-off smoke exposure increases our long-term risks of heart disease or cancer is unclear, the health department said. “Short term infrequent exposures probably do not have much effect, but long-term exposure to particulate pollution, like urban smog, increases the chance of heart disease. In terms of cancer, we know that urban firefighters have higher rates of lung cancer compared to other people, but it would probably take a great deal of exposure to wildfire smoke at the community level to produce a measurable increased cancer risk.”

How do the masks we use for Covid-19 work for smoke and what are other options?
Most cloth masks worn for Covid-19 will not be effective against smoke like the Eastern Sierra is dealing with this month, the health department said.

“Dust masks and surgical masks do not reduce our exposure to particulate pollution,” the health department said. “N95 or N100 masks, technically called respirators, can greatly reduce inhalation of smoke particles if they fit properly, which means tightly.

“Leaky masks won’t provide much protection,” they said. “Properly fitting N95s are a bit hard to breathe through and may not be practical for use over many hours or days. They may also be hard for vulnerable people, such as elderly and people with lung disease, to tolerate. If you choose to try one, the state health department website has information about N95 masks (Go to: https://www.cdph.ca.gov/Programs/EPO/Pages/Wildfire%20Pages/N95-Respirat...).”

How do we keep the smoke from being unhealthy indoors?
“When smoke levels reach potentially unhealthy levels, we recommend that people stay indoors as much as possible, with windows and doors closed, swamp coolers off and air conditioners on recirculate, if they have that function,” the health department said. “In hot weather, that may feel like being between a rock and a hard place - balancing the possible harm from smoke against that of heat. There are indoor air cleaners or filters that can improve air quality, removing smoke particles, they said. “
The most effective are filtering systems installed in the ductwork of homes. There are also smaller portable cleaners that can effectively clean indoor air, if their capacity is appropriately matched to the size of the indoor area.”

For those people who are at higher risk for severe illness from Covid-19, or if you cannot install air filters in your ductwork, like most renters, you can create effective home clean rooms as a practical way to both reduce smoke exposure and maintain social distancing, the health department said.

“Anyone can benefit from creating a clean room, but it is especially important for people with health conditions that might increase their risk of illness or injury effects after wildfire smoke exposure,” they said. “Clean rooms at home are also recommended for people who must work outside, so they can access a space with clean air while indoors at home after work.”

This means creating at least one room in your home where you focus your air filter system, or you keep the doors and windows tightly closed at all times. Once the smoke gets into a room in the first place, it is hard to get out. So, choose at least one room, preferably with few windows, or windows that are tightly sealed, to focus on and keep kids, dogs and other door-openers out! If the smoke has already gotten into all rooms, wait until there is a big break in the smoke, then air out that room thoroughly, then seal it again before the smoke rolls in and keep it sealed, except to use it carefully.

Can I retreat to my vehicle and use AC if the smoke gets bad?
Vehicles should be used for transportation, not to shelter from smoke, the health department said. “Recent model vehicles tend to have air filters that do a decent job of removing particulate pollution if set to recirculate with doors and windows closed. But during warm days, such as in summer, rising temperatures and carbon dioxide levels inside the car may limit the feasibility of using recirculation for long. Because carbon dioxide levels can rise quite quickly on recirculation it is advisable to periodically open windows.

What if none of this works?
Smoke-sensitive people who are unable to sufficiently reduce their smoke exposure at home may want to leave the area during major smoke incidents if it is feasible and there are places with better air quality. However, this must be balanced against the risks of traveling in the Covid-19 pandemic and the chance that heavy smoke could make driving more dangerous due to reduced visibility.


• Great Basin Unified Air Pollution Control District: https://www.gbuapcd.org

• Airnow.gov was recommended as the most accurate site to assess the smoke level in your city or community. Mammoth’s monitor is on top of the RiteAid building Go to (https://fire.airnow.gov/). This provides current air quality information in terms of the Air Quality Index, or AQI, a nationally standardized system for pollution reporting that some people may be more familiar with.

• The U.S. Forest Service has a helpful site that provides a 72-hour forecast of wildfire smoke conditions: https://tools.airfire.org/websky/v2/run/standard/CANSAC-1.33km/current#v...

• Visit the Center for Disease Control and Prevention’s (CDC)s “Public Health Strategies to Reduce Exposure to Wildfire Smoke during the COVID-19 Pandemic” online at: https://www.cdc.gov/disasters/covid-19/reduce_exposure_to_wildfire_smoke...

• Go to the California Air Resources Board at (https://www.arb.ca.gov/research/indoor/aircleaners/consumers.htm). It has valuable information about indoor air cleaners and maintains a list of approved products. Air cleaners which generate ozone are not recommended.