Across the United States, approximately 73,200 wildfires burn over 6.9 million acres every year.
As of November 30, 2018, 52,303 wildfires have blazed over 8.54 million acres, and more are reported every day — from California to Maine, the number of wildfires appears to increase every year. Thanks to the tireless efforts of firefighters and emergency responders, most wildfires are quickly controlled. But what are their long-term impacts on our environment, including our air quality?
Wildfires are a natural occurrence, and they provide many benefits for an ecosystem. However, they also come with a list of negative impacts, including damaging the quality of your air.
How and Where Wildfires Occur
Also called a forest fire, vegetation fire, grass fire, peat fire or a hill fire, wildfires are a common occurrence in many areas of the country.
Not every fire is considered a wildfire. According to the National Wildlife Coordinating Group, a wildfire is an unwanted and unplanned wildland fire, and it includes the following categories:
- Unauthorized, human-caused wildland fires: Humans cause more than four out of every five wildfires — according to a NASA study, up to 84 percent of all wildfires are a result of human carelessness. Since the 1940s, wildlife experts have used campaigns like Smokey Bear to urge guests to be cautious in nature. A spark from a campfire, a cigarette tossed out a window or a stray firework could all lead to a wildfire under the right conditions. Sometimes, human-caused fires are set intentionally as an act of arson, but these are much rarer than accidental fires.
- Escaped prescribed wildland fires: Wildlife officers will sometimes schedule a prescribed burn for a certain area. Many prescribed fires, also called controlled burns, are set every year to rejuvenate land and return it to a thriving state — controlled burning has a long history of positively impacting wildland. However, if these prescribed burns escape control, they are considered a dangerous wildfire.
- Escaped naturally caused wildland fires: Naturally occurring wildfires can be caused by a variety of incidents, including lightning strikes and volcanic eruptions. Under the right conditions, hot winds or even direct sunlight can be enough to start a blaze. When natural wildfires occur on wildland, wildlife officers will often let it burn in a controlled, monitored manner. However, if it looks like it will threaten human habitation, federal firefighting teams will begin to put it out.
- Other wildland fires: Fires can begin for other reasons, and they are considered wildfires if they threaten human communities or the environment.
For a wildfire to occur, the conditions have to be just right. Droughts, heat waves and other cyclical climate changes can dramatically increase the chance of a wildfire — if a field or forest is dry due to a months-long drought, it will catch fire easily and spread quickly. Additionally, if high winds are present, the breeze can pick up sparks and spread the fire even faster.
A wildfire needs three conditions to burn — fuel, oxygen and a source of heat. Together, firefighters refer to these conditions as the fuel triangle. In the triangle, fuel refers to any flammable material close to a fire — brush, grass, trees, crops or buildings could all feed a wildfire. Generally, the greater an area's fuel supply, the more intense of a wildfire it can support.
Wildfires fall into three broad categories based on where they burn in an environment — surface, crown and ground fires.
- Surface fires: The most common type of wildfire, surface fires tend to move slowly and burn the forest floor, damaging and killing all low-lying vegetation.
- Crown fires: Crown fires are spread by wind and move quickly along the tops, or the crowns, of trees. These types of wildfires are especially damaging to woodlands.
- Ground fires: A lightning strike to grassland or a forest often starts ground fires. The lightning ignites underground coal, peat or root systems and spreads, often burning through to the surface and becoming surface fires.
Wildfires can begin anywhere. However, they are most common in forested or vegetated regions such as grasslands or scrublands. These areas receive enough moisture to support foliage growth, but they also experience extended dry, hot periods that leave plant material vulnerable to fire. Wildfires are especially common during summer, autumn and early winter months when fallen leaves and branches tend to dry out and become flammable.
The Environmental Effect of Wildfires
As earth temperatures rise and urban expansion extends into wooded or wild areas, we are more likely than ever to feel the impacts of wildfires. However, not every effect of a wildfire is negative — wildfires can create positive conditions as well.
1. The Positive Effects
For the environment, wildfires aren't always tragic — some ecosystems depend on regular fires for regeneration, reproduction and germination. A wildfire clears away brush and dead foliage, leaving behind new growing space and fresh, fertilized soil. Some species of pine trees only reproduce in the presence of extreme heat, and without wildfires, they would gradually go extinct.
For the environment, a wildfire can have the following positive effects:
- Clears away dead or overgrown foliage: Over time, a forest floor gets cluttered with shrub growth and the accumulation of dead trees and plants. Because so much space is taken up by undergrowth, new plants are unable to thrive in the ecosystem. A wildfire clears out any low-standing plant life, clearing the way for new, abundant growth. Many ecosystems rely on this periodic cleansing to remain healthy — fire acts as a kind of disinfectant, removing harmful insects and diseased plants from the ecosystem.
- Fertilizes soil: As a wildfire turns dead and decaying plant matter to ash, it releases nutrients into the soil. This is why so many wildflowers bloom after a wildfire has died out — the sudden influx of nutrients is conducive to new growth.
- Helps seeds germinate: Some species of plants and trees need wildfires to thrive — they can only successfully reproduce in the presence of intense heat. Some examples of fire-adapted plants include lodgepole pine, Jack pine, hickory pine, redberry and eucalyptus. When exposed to a fire, the seeds of these plants can open or germinate, spreading new life after a wildfire.
- Revitalizes the watershed: By cycling nutrients, replenishing stream-bank vegetation, increasing food sources for fish and dispersing fire-adapted plants, wildfires can revitalize watershed environments.
Although most people associate wildfires with danger or destruction, they are a vital part of the ecosystem and provide many benefits for natural environments.
2. The Negative Effects
But a wildfire can cause damage, as well. When a naturally occurring wildfire swells and reaches out-of-control proportions, it can threaten human property and communities
- Hurts air quality: A wildfire releases substantial levels of pollutants into the air, including vast quantities of smoke. This smoke consists of partly consumed fuel, ash particulates, invisible gases and liquid droplets. While brief exposure to smoke does not create long-term damage, high smoke concentrations can lead to health complications, especially for those with respiratory issues or illnesses. Some effects of prolonged smoke exposure include impaired judgment and alertness, the development of chronic illness and asthma triggers.
- Damages soil: Although a wildfire can release vital nutrients into the soil, it can also damage the delicate soil balance — by burning away the protective litter layer, the soil is vulnerable to erosion. The heat of intense wildfires can also change the soil composition, making it resistant to water and prone to aridity.
- Injures or kills plant life: No matter the type of fire, a wildfire harms plant life. While this is sometimes needed for the health of the ecosystem, a wildfire doesn't discriminate between plants — it destroys everything in its path, even if the plant was endangered, beneficial or ancient.
- Increases runoff: After a fire, the soil is often unable to absorb water for some time. Any rainfall or water becomes runoff, flooding lakes, streams and rivers with sediment and debris. Areas affected by wildfires are often vulnerable to flash flooding once the fire has been extinguished.
Wildfires carry both positive and negative effects for the environment, and every area is impacted differently depending on the location and intensity of the fire.
How To Stay Safe From a Wildfire
As a property manager or homeowner, you can take steps to reduce the potential of damage before a wildfire hits your property. One of the most important precautions is to limit any fuel sources around your business or home.
Clear away any combustible materials from within 30 feet of your buildings — these include dried leaves, pine needles, vines and dead or dry vegetation. Between 30 and 100 feet away from buildings, make sure your property has "fuel breaks" such as driveways, sidewalks or gravel pathways. Pavement or stones are a non-flammable surface, and they help to keep the fire from spilling onto your property.
If your area is in the path of a wildfire, the most important thing is not to panic. Today, firefighting responders use expert techniques and strategies to suppress a fire quickly. While first responders control the blaze, follow these steps to stay safe during a wildfire:
- If you are advised to evacuate your home or location, leave as soon as possible.
- Wear protective clothing and closed-toe shoes. Protect yourself from smoke and limit any time spent outdoors.
- Lock doors, windows and any remaining vehicles.
- Close all windows and doors to reduce heat and prevent drafts from entering your home, and make sure to shut off natural gas from its source.
- Turn on all the lights on your property to help firefighters easily see it through dense smoke.
- Tell someone that you have evacuated and where you are planning to go.
- Choose a safe route of evacuation, far-removed from fire hazards. As you travel, check your local weather channel for information on the speed and direction of fire and smoke — if the fire appears to change direction and head towards you, choose an alternate route.
- During the fire, stay informed about the status of the wildfire. Pay special attention to local weather forecasts, particularly any that could affect the fire conditions.
Don't return to your home prematurely — keep away from your property until officials declare that it is safe to access.
Post-Wildfire Protection Tips
Even after firefighters have put out a wildfire, your property could remain dangerous. Don't return to your home or business until officials declare it safe — even after a fire has been put out, small blazes can flare up unexpectedly.
Beyond small residual fires, the larger effects of a wildfire linger well after the flames are put out. A few of the post-wildfire dangers include:
- Road instability: Drive carefully in areas affected by wildfires — the intense heat can damage and weaken roads, making them more prone to surface erosion.
- Flash flooding: Keep an eye on your local weather forecast for flash flood warnings, and create a flooding emergency plan for you and your family.
- Structural damage: Most structures and buildings damaged by fire are unstable. Don't enter any building until emergency officials have examined it.
- Unstable trees and power poles: After a wildfire, use caution around power poles, trees and any other tall objects that could have lost stability from burn damage.
- Contaminated water systems: A wildfire often damages water lines and systems. Don't drink or use any water from the faucet until your water system has been cleared by emergency officials.
Before you begin any cleanup efforts, make sure to take pictures of the damage to your property to send to your insurance carrier.
Testing Air Quality After a Wildfire
In the wake of a wildfire, smoke, ash and toxins remain in the air. Even if the fire did not damage a building, cleaning efforts around the area disturb soot and ash, sending fresh clouds of particulate matter and gaseous chemicals into the air.
Additionally, once a fire begins to spread through an urban setting, the smoke becomes more hazardous to human health. Instead of just burning plant matter, the air is now filled with the synthetic and chemical compounds released as fire burned away manufactured objects and materials.
The effects of poor air quality vary from person to person, but common complications include:
- Asthma triggers
- Acute irritation
- Immune system suppression
- Reduced lung capacity
Fortunately, there are measures you can take to determine what hazardous compounds, if any, are in your air. If you are concerned about the state of your air, consider testing your air quality. An air test could determine whether the following fire-related pollutants are present in your air:
- Smoke particles and residue
- Carbon monoxide
- Nitrogen dioxide
- Acetic acid
- Heavy metals
Testing your air quality after a wildfire helps you know what toxins are present in your home. Once you know the types and levels of contaminants in your air, you can begin accurate cleaning or filtration, quickly restoring your air to its previous condition.
Air Sampling Equipment to Use After a Wildfire
You can purchase a variety of air sampling equipment in the wake of a wildfire. The most common way to sample air quality is through an air sampling pump that is collecting airborne particulate onto a filter media.
Sophisticated and reliable, air sampling pumps and media are an effective method of sampling air quality. When air sampling pumps are paired with the appropriate filter, they help technicians and industry experts analyze for a wide variety of hazardous compounds, including airborne particulates, metals and asbestos fibers. Pumps come in large area-scale models or smaller personal sizes for optimal personal exposure assessment.
Another product that is widely used in the determination of wildfire origin is the Zefon Bio-Tape™. Taking a surface sample with the Zefon Bio-Tape™ provides a standardized sampling method and can be used to identify the origin of wildfire damage to a home. The sample lifted from the surface is analyzed for microbial, bioaerosol and inorganic dust contamination within the home.
When it comes to air quality, don't leave anything to chance. Professionals from a range of industries choose Zefon International products to safely and quickly collect samples of air quality.
At Zefon International, we take your health and safety seriously. We are industry-leading manufacturers and a long-standing partner with air quality experts, and we offer the highest quality products and customer service.
We are the professional choice for air sampling equipment — browse our products or contact us, and let us help you test your air quality today.