Wildfire and extreme heat season is here: do you know when you should close your patio?

It’s become almost a yearly event. Smoke from nearby wildfires hangs over the area, creating hazardous conditions for anyone working or enjoying the outdoors. Cities across the state often wake up to smoky conditions during the hot summer months, starting earlier in the year. So, how can you know when the air is too unhealthy for workers and your guests?

We expect new guidance surrounding heat rules from L&I in June, but here are some tips to help you until then:


Employers must monitor temperatures throughout the day and protect employees from heat-related illnesses when temperatures reach 57 degrees and workers are wearing non-breathable clothing, such as rain gear; 77 degrees when employees are wearing double-layer woven clothing like sweatshirts; and 89 degrees when wearing any other type of clothing.  

When temperatures reach 89 degrees or hotter, employers must: 

  • Provide outdoor workers enough sufficiently cool water to drink at least a quart an hour 
  • Provide adequate shade that is large enough and close enough to workers 
  • Encourage workers to take paid preventive cool-down breaks as needed  
  • Require a paid 10-minute cool-down break once every two hours

Employers must train employees to recognize the signs or symptoms of heat-related illness and implement a plan for communicating these signs. They must also develop an outdoor heat exposure response to their Accident Prevention Plan. You can find an example of this addendum on L&I’s website. 

Learn more about L&I’s emergency heat exposure rules here. You can also find this card that includes prevention and symptoms in English and Spanish here. 

Smoke exposure

Remember: health officers have the authority to shut down any outdoor event or space with unhealthy air quality.

What you need to know

Download the EPA AIRNow app for your iPhone or your Android device. This app will describe air conditions in your area.

Download the following photo, print it out and post in your office to remind everyone when it is time to close the patio.

Click this photo to download a printable version.

In its newsletter, Spokane Regional Clean Air Agency recently included an article from former Spokane Regional Health District Health Officer Bob Lutz that explains the hazards of smoky air.

“Smoke from wildfires is a complex mixture of substances that includes water vapor, heavy metals, hydrocarbons, gases such as carbon monoxide and ozone, and particulates.

“While the general effects of smoke often irritate the eyes, nose and throat, the greatest concern is caused by the smallest particles, PM2.5. These can get deep into the lungs, be absorbed into the blood and cause inflammation throughout the body. Their effects can worsen pre-existing conditions, such as asthma, COPD, and heart disease. Additionally, infants and children, adults over age 65 and pregnant women are at increased risk from exposure. And those who cannot get out of the smoke, such as individuals living homeless, are likewise impacted.

“The reality, however, is that everyone is at risk, because there is no safe level of PM2.5. Studies have shown increased healthcare visits as well as increased hospitalizations and even deaths, both during and soon after periods of poor air quality from wood smoke.”

Useful websites during wildfire events:

It’s important to note that air quality sites don’t report the air quality in real-time but an average of the last 24 hours.

How do you know when to close your patio?

According to the Department of Labor & Industries:

“The AQI indicates when the outdoor air quality is ‘unhealthy,’ ‘very unhealthy,’ or ‘hazardous.’ These ratings signal when healthy workers may begin to experience adverse health effects. Additional factors to consider when determining if the outdoor air is harmful include how long workers are outside, the level of physical exertion, symptoms consistent with wildfire smoke exposure, and pre-existing medical conditions.”

When air quality is in the unhealthy range, you will want to check your HVAC system’s filters–the higher MERV, the better. You will also want to check all the doors and windows to make sure they have good seals. The idea is to minimize the amount of air coming into your restaurant or hotel. For more information on indoor air quality, read this flyer from the Washington State Department of Health.

Watch this video: How to make a clean air fan