Getting to Know You: Ground Level Ozone

by SLCgreen intern Emalee Carroll

As Salt Lake City residents we are well acquainted with air pollution, but do we know what’s in it? With the Clear Air Challenge happening over the summer, we at SLCgreen wanted to take some time to provide a rundown on some of the different types of air pollution in Salt Lake City, what you can do about it, and what the city is currently working on and has done to make a difference!

What is Ground Ozone? 

As we enter the thick of summer and all the fun outdoor activities that come with it, let’s break down a major summertime pollutant – ground level ozone. Ozone gas is naturally occurring in our atmosphere, helping to protect us from harmful UV radiation. However, ozone is not found naturally at ground level. Rather, the gas is known as a “secondary pollutant” meaning it’s created through a series of reactions between compounds in the air. This process is facilitated by heat and sunlight which is why ozone levels are typically higher in the summer months. 

How does Ozone Affect SLC residents? 

Like PM 2.5, studies have shown ozone also has adverse impacts on respiratory health. Ozone gas can reach deep into our lungs, damaging cells like a sunburn would, and trapping air in the alveoli. This process can cause coughing, throat irritation, chest pain, and congestion. Additionally, ozone can aggravate respiratory diseases such as asthma, COPD, and chronic bronchitis. 

Aside from harming the health of Salt Lake residents, ozone can also negatively impact local ecology. When ground-level ozone enters the membranes of leaves, it reduces the ability of the plant to photosynthesize sunlight, slows growth, and ultimately weakens the organism. In extreme circumstances, this can lead to a loss of trees and other plants, which affects both the quality of life in urban settings, as well as the health of the overall ecosystem and animals that rely on those plants for food. 

What can you do? 

Here are some easy ideas to reduce ground-level ozone 

1. Avoid unnecessarily idling your car. Idling is more damaging than driving for the environment, the engine, and your pocketbook. Research has shown that idling for just two minutes is equivalent to one mile of driving. With increasing gas prices, idling your car and wasting gas will force you to fuel up more than necessary.  Depending on the type of car and gas prices, studies have found that idling can cost at least $70 a year. A good rule of thumb is to turn your car off if you’re stopped for more than 10 seconds unless in traffic!  

2. Pump gas at night or before the hottest hours in the day. The fumes released when getting gas are the same ones that go on to form ozone. However, when you fuel up at night, these compounds lack the sunlight and heat required to convert to ozone. If you can’t fill up at night, fuel up in the morning. Avoid getting gas during the hottest parts of the day.  

3. Mow your lawn in the morning.  Similar to the above, if you have a gas-powered mower or other landscaping equipment, don’t use it in the middle of the afternoon or early evening.  Mowing in the morning will prevent as much ozone from forming. Better yet—move to all-electric mowers or push mowers! 

4. Avoid single-occupancy vehicle trips. Carpool, bike, walk, or use public transportation instead. Single-occupancy vehicle trips are responsible for a large share of SLC’s ozone. If you can, opt to carpool, walk, bike, or use public transportation.  You can also “skip the trip” until a day or time when the ozone forecast is not as high.  If you are in the market for a new vehicle, consider an all-electric option which doesn’t produce local air pollution! 

5. Avoid participating in outdoor activities after the workday begins. While this does not impact ozone, this does protect your health. Once people begin commuting throughout the day, ozone levels increasing, making afternoon or evening runs harmful to your health since that’s often when ozone is at its worst. Instead, go for a run or bike ride in the morning when temperatures are cooler, and the ozone pollution has diminished throughout the night. 

What is SLCgreen doing? 

Page BreakHave we talked to you about the Clear the Air Challenge?  

With many of our 3,000 city employees participating, we are helping to contribute to the elimination of 100,000 trips, saving of 2,000,000 miles, and reduction 375 tons of CO2, which is the goal of this year’s statewide Challenge! That might seem like a lot, but in 2020, Utahns helped reduce 476 tons of pollution, 100 tons more than in 2019. If you’d like to join in the challenge, look for “SLCgreen” in the teams option on the Clear the Air Challenge website dashboard and help us Clear the Air! 

SLCgreen is also working to produce quality long-standing projects and policies that will reduce the city’s ground-level ozone levels today and into the future. For example, Salt Lake City evaluates all new city-funded construction above a certain threshold to meet Net Zero and LEED Gold standards LEED Gold is the premier sustainable building standard which ensures new construction is healthy, highly efficient, and cost-saving. Having energy efficient infrastructure decreases our reliance on many of the processes that emit ozone precursor emissions.  

Other key priorities include: 

• Creating Air Quality Action Day alerts, urging eligible employees to telework and take other practices to reduce emissions during Mandatory Air Quality Action days. 
• Funding the annual exchange of gas-powered lawnmowers and other equipment for clean, electric options. 
• Supporting “EV-ready” infrastructure in new multi-family buildings. This proposed update to zoning code was just approved by the Planning Commission on July 13 and will be making its way to the City Council later this year. 
• Transitioning the Salt Lake City fleet to more and more electric vehicles 
• Supporting clean, combustion-free buildings through the RDA 
• Implementing the annual Energy Benchmarking ordinance 
• And much more! 

Supporting Clean Electricity 

In addition to helping clear the air in the valley, we’re also supporting clean energy for our electricity grid across the state. The “Utah 100 Communities”, aims to provide Salt Lake City residents, along with 17 other communities in the state, net-100% renewable electricity by 2030 or before. 

This project will help to improve air quality across the state, and not just in the valley!