Image above provided courtesy of Brightline Defense.
TL;DR — Construction is a well-known producer of air pollution that negatively impacts both human and environmental health via the emission of particulate matter and volatile organic compounds, among other harmful pollutants. Construction activities and equipment alike also contribute to climate change through the release of greenhouse gases. By understanding the ways that construction negatively impacts the immediate environment, those working at the site, and nearby communities, we can take action to minimize these harms through increased regulation and sustainable practices.
The impacts of the construction sector
Construction zones are a known source of significant amounts of air pollution — in addition to water, noise, and soil pollution — that can affect nearby homes, businesses, and residents.
Construction also generates a large amount of waste. In the U.K. alone, the construction sector uses over 400 million tons of material per year.
Data from the United States shows that construction contributes significantly to pollution, including:
- 23% of air pollution
- 40% of drinking water pollution
- 50% of pollution related to climate change
- 50% of the environmental pollution from landfills
Construction accounts for 30% of particulate matter (PM10) emissions, 8% of fine particulate matter (PM2.5) emissions, and 4% of nitrous oxide emissions in London according to the 2019 London Atmospheric Emissions Inventory.
Construction also significantly impacts climate change, with 25-40% of the world’s carbon emissions being attributed to construction activities.
How does construction affect air quality?
The construction sector has a significant detrimental impact on air quality.
According to a UK-based source, the construction industry has actually increased its overall share of emissions in recent decades as compared to other sectors, like transportation, which have decreased their share through policies such as ultra-low emission zones. This may be due to the construction sector receiving less attention for its polluting effects coupled with a tendency to have less strict air quality regulations.
Key pollutants involved in construction-related air pollution
One major source of construction-related pollution comes from the dust produced during construction and demolition activities — including excavation, loading and unloading, preparing raw materials, and road construction. This dust contains particulate matter and volatile organic compounds that can be spread around the construction area and surrounding neighborhood via wind.
Demolition activities can also expose both construction workers and nearby residents to mold, asbestos, lead, bird waste, and other respiratory irritants.
Construction also produces greenhouse gas emissions when diesel and fossil fuels are burned to run machinery. The production of finished concrete generates a significant amount of carbon dioxide emissions.
Particulate matter is one common air contaminant in construction zones that poses major damage because of its significant harm to human and environmental health.
Some activities that produce PM include equipment travel, on-site material handling operations, and equipment exhaust.
Construction sites are responsible for 14.5% of particulate matter in the air and 8% of total emissions in the United States”
— Facility Executive
For more information on the harms of particulate matter air pollution, read our air quality measurements series blog here.
Volatile organic compounds (VOCs) are another type of air pollutant that acts as a major player in construction-related pollution.
The American Lung Association defines VOCs as emitted gases that are both harmful on their own — as some are known to be cancer-causing — and that can react with other gases in the air to form other dangerous pollutants. Some common VOCs include benzene, formaldehyde, and toluene as well as the carcinogenic trichloroethylene and vinyl chloride.
VOCs can be emitted from a wide variety of sources and construction activities, including:
- Tile adhesive
- Roofing materials
- Other building materials
- Natural gas
- Cleaning products
Wind speed and direction can also be helpful to monitor in order to determine how pollution originating from a construction site is traveling and affecting the surrounding area — similar to the way that anemometers are important around mining and other industrial operations. To learn more about the importance of air quality monitoring at mining and industrial operations, read our blog here.
Read our air quality measurements series blog on wind speed and direction here to learn more about how wind measurement helps paint a complete picture of air pollution.
In addition to the myriad of negative health impacts caused by air pollution from construction zones, polluted air can reduce visibility and even lead to accidents at major roads and intersections.
How construction machinery and equipment result in air quality degradation
The use and type of construction equipment also play a role in producing air pollution.
A lot of construction machinery and vehicles run on diesel fuel, which releases a number of pollutants into the air — including carbon monoxide, carbon dioxide, nitrogen oxides, and hydrocarbons. Diesel-powered equipment is also a major source of greenhouse gas emissions, exacerbating climate change. Especially on large-scale construction projects, the equipment can be running for an extended period of time, thereby creating more pollution.
Importantly, construction machinery is not regulated by the government to the same degree as other vehicles such as passenger vehicles. Because of the significant amount of pollution these vehicles can release, it is essential that they are more strictly regulated.
The impacts of asbestos
Though asbestos is most well-known to impact indoor air quality, it can also impact outdoor air, especially via construction activities.
Unfortunately, asbestos has a long history of being used in construction materials. Up until the 1970s, it was used in a variety of building materials, including insulation, floor and ceiling tiles, countertops, siding, and shingles.
Asbestos fibers are present in low levels in soil, water, and air — meaning that everyone can be exposed to asbestos at some point in their life, though these low levels do not usually negatively impact health. However, the problem comes when asbestos-containing materials degrade or are not properly contained during construction and become released into the air, where they can be inhaled into the lungs.
Asbestos can remain in the air for long periods of time and, like other pollutants, can be carried by wind and contaminate areas away from its original source. Asbestos does not biodegrade and, thus, can cause significant damage to human health.
Keeping the air clean during construction: best practices and control measures
While construction activities can cause significant amounts of air pollution, there are fortunately some ways to reduce these impacts.
Some potential practices include designing more sustainable construction projects, using more sustainable and pollutant-free building materials, minimizing the discharge of pollutants created at the site, and setting emission reduction targets to prioritize the reduction of air pollution produced by the project.
One key practice to reduce the impacts of a construction project is to establish a high-resolution air quality monitoring network. You can’t manage what you can’t measure, so it is essential to understand the pollution levels affecting the site and surrounding communities.
Dust control measures
Many construction sites implement dust control measures because dust can significantly contribute to PM2.5 and PM10 levels. This is often carried out through sprayers, mist cannon, or sprinklers that spray water over the area to reduce dust being taken up into the air.
Some sites instead sprinkle or irrigate the ground with water. However, as with traditional water sprayers, water must constantly be reapplied and can be an inefficient method.
Other methods include having vegetative cover around the areas used for vehicle traffic where vehicles can stir up dust or placing mulch over a recently disturbed area. Research shows that mulch can be an effective solution, as it reduces wind erosion by 75-95%.
Windbreaks can also be useful as they reduce the wind speed in a given area, thereby reducing the number of particles that become suspended.
Dust control practices reduce the potential for construction activities to generate dust from disturbed soil surfaces. Construction sites can have large areas of soil disturbance and open space from which wind can pick up dust particles. Airborne particles pose a dual threat to the environment and human health.”
The US EPA also notes that it is especially important for dust control measures to be employed in arid or semiarid regions, where it is easier for soil to become dry and be transported by high winds. For the most effective action, dust control measures should be designed depending on the site’s specific topography, land cover, soil characteristics, and expected rainfall.
Proper waste management and disposal to minimize airborne pollutants
In addition to construction activities producing air pollution as they are occurring, they can also produce a significant amount of waste. According to one estimate, construction produces one-quarter of the world’s waste.
This waste mainly comes from construction and demolition materials and accompanying debris.
In order to reduce this large amount of waste, it is vital to make operations more efficient, choose technologies that help in waste reduction, and optimize the use of construction supplies and materials.
Reducing this waste and properly disposing of construction materials means less airborne pollutants and improved environmental health.
Utilizing low-emission construction machinery and equipment
Construction machinery itself emits harmful air pollutants and greenhouse gases that negatively impact the environment.
Some low- and zero-emission construction machinery exists — such as battery-powered zero-emission equipment — and increasing its use will be beneficial to reducing construction’s detrimental impacts on the air. This equipment also releases zero greenhouse gas emissions and tends to contribute less to noise pollution.
The electrification of construction machinery is moving forward and proves more promising than that of agricultural equipment. Construction often takes place in more urban areas with greater infrastructure and involves more compact equipment, both of which make it easier to move towards electric equipment.
Regular maintenance and calibration of air quality monitoring devices
Air quality monitoring in construction zones is a vital part of minimizing the negative impacts that construction activities have on both human and environmental health.
Real-time monitoring of construction sites has many benefits, not the least of which is the health and safety of construction site workers. Without real-time insights of on-site PM pollution conditions, construction site workers could not assess the safety precautions that should be undertaken while on the job.”
— Facility Executive
It is highly important to regularly maintain and calibrate air quality monitoring devices to ensure the most accurate and reliable data is collected and can be used to drive decision-making.
The regulatory framework and sustainable practices surrounding construction-related air pollution
Because of construction’s significant negative impacts on air quality, many countries and agencies around the globe have put into place regulatory frameworks to manage pollution exposure.
In California, Cal OSHA states that employers have to provide respirators for employee use when the AQI for PM2.5 is between 151 and 500 that day. After the AQI surpasses 500, the employer must require respirator use.
Similarly, Washington’s Labor and Industries Department requires that employers monitor air quality and protect outdoor workers who are exposed to heightened levels of air pollution, beginning when the AQI reaches 69 or higher.
Because California and Washington are in regions that are prone to wildfire, these regulations also help to protect workers from wildfire smoke exposure in addition to other sources of outdoor air pollution, such as construction.
Saudi Arabia has also recognized the impacts of construction activities on air pollution. The Ministry of Environment has included these emissions under the umbrella of industry-related emissions and has put regulations in place accordingly.
Recognizing the impacts of air pollution on construction workers — whether due to pollution produced at the site or from other sources that they are exposed to, such as wildfires — and establishing regulations is essential in protecting those working at the site who may have the greatest risk of harmful exposure.
Cleaner construction for cleaner air
Construction has clear detrimental effects on air quality and climate change, but by recognizing these impacts and potential solutions, we can work toward a future of cleaner air.
Establishing a high-resolution air quality monitoring network is the first step in quantitatively measuring the impacts of both the construction activities themselves and the action taken to reduce their harm.
By prioritizing sustainable construction practices, such as switching to low- or zero-emission equipment, carrying out dust suppression and waste management practices, and establishing air quality monitoring networks around construction zones, we can reduce the negative impacts of construction-produced air pollution.
Interested in measuring air quality for cleaner air, improved physical and mental health, and a healthier climate? Get in touch with our team to learn more about our Sensing-as-a-Service solution for governments, businesses, and community organizations, using our Clarity Node-S monitors and modules that do not depend on infrastructure like WiFi or power — making them especially resilient during environmental disasters and flexibly placed around pollution sources such as construction zones.