Pollution's Impact: The Slow Decay Of Our Buildings

Burning fossil fuels to power buildings releases harmful pollutants that affect both the indoor and outdoor air quality. These pollutants, such as nitrogen dioxide, sulfur dioxide, and carbon monoxide, can have direct and indirect impacts on human health and the environment. The presence of these air pollutants interacts with building materials, causing aesthetic and structural damage. Additionally, the design and construction of buildings can impact air quality, and climate change may worsen indoor air problems.

Particulate matter (PM2.5) from buildings can enter the lungs and bloodstream

Particulate matter (PM2.5) is a dangerous pollutant due to its tiny size. These particles are so small that they can be inhaled and penetrate deep into the lungs and even the bloodstream. The particles are released from the combustion of gasoline, oil, diesel fuel, or wood, and can enter indoor spaces through doors, windows, and leakiness in building structures. They can also form indoors through complex reactions of gaseous pollutants emitted from household cleaning products, air fresheners, smoking tobacco, cooking, and burning wood, candles, or incense.

PM2.5 is a complex mixture of solids and aerosols composed of small droplets of liquid, dry solid fragments, and solid cores with liquid coatings. They vary widely in shape and chemical composition and may contain inorganic ions, metallic compounds, elemental carbon, organic compounds, and compounds from the earth's crust. Due to their small size, they pose a significant risk to human health.

Short-term exposure to PM2.5 has been linked to premature mortality, increased hospital admissions for heart or lung-related issues, acute and chronic bronchitis, asthma attacks, emergency room visits, respiratory symptoms, and restricted activity days. These adverse effects are more commonly seen in infants, children, older adults, and individuals with pre-existing heart or lung diseases. Long-term exposure to PM2.5 has also been associated with premature death, particularly in those with chronic heart or lung conditions, and reduced lung function growth in children.

The effects of PM2.5 on buildings are not limited to health consequences. These particles can also cause aesthetic and structural damage to the building materials. The physical and chemical properties of building materials can be altered by the presence of gaseous and particulate air pollutants, which trigger reactions that change the composition of the materials. This can lead to structural damage and impact the health of the residents occupying the building.

Overall, particulate matter (PM2.5) from buildings can have significant impacts on both human health and the structural integrity of the buildings themselves. The tiny size of these particles allows them to penetrate deep into the lungs and bloodstream, causing a range of adverse health effects, while also affecting the building materials through complex interactions with pollutants.

Air pollutants cause aesthetic and structural damage to buildings

Air pollutants can cause aesthetic and structural damage to buildings in several ways. Firstly, the increase in air pollutant concentrations in the ambient air leads to a higher number of pollutants interacting with building materials. This interaction is further influenced by factors such as sunlight and biological agents, resulting in complex chemical reactions that alter the composition of the materials. The physical and chemical properties of building materials are significantly affected by the presence of external agents, which can be natural or anthropogenic. Gaseous and particulate air pollutants, such as sulphur dioxide, ozone, chlorides, nitrogen dioxide, nitrates, and carbon dioxide, act as external agents triggering reactions that change the composition of building materials.

The recirculation of air pollutants in urban areas, known as the "canyon effect," caused by the proximity of high-rise buildings, further increases the exposure time of pollutants to buildings, resulting in greater damage to the building materials. Additionally, meteorological conditions can prevent pollutants from dispersing to greater heights, causing them to remain at lower levels and interact with buildings, leading to structural damage.

The chemical reactions involving the transformation of building materials can result in the formation of sulphates and the release of carbon dioxide. For example, the exposure of sulphur dioxide to calcareous materials can lead to the formation of gypsum on the surface.

Furthermore, the wet deposition of O3 and H2O can accelerate the deterioration of building materials. As the concentration of air pollutants increases, the compressive strength of building materials decreases, making them more susceptible to damage. Acidic air pollutants can penetrate deep into the building material, causing structural damage and triggering further physical, chemical, and biological reactions that may affect the health of residents.

Overall, the presence of air pollutants can have significant aesthetic and structural impacts on buildings, leading to complex interactions and transformations that can be detrimental to both the building's integrity and the well-being of its occupants.

Tall buildings affect the dispersion of pollution within neighbourhoods

The presence of tall buildings in a neighbourhood can have a significant impact on the dispersion of pollution, leading to the creation of "dead-zones" and "hotspots" of high pollution concentration. This phenomenon is influenced by various factors, including the height and arrangement of the buildings, wind speed, and wind direction.

In London, UK, for example, the recent construction of numerous high-rise buildings, including the Shard, which stands at a height of approximately 310 meters, has altered the city's landscape. This changing cityscape prompted a detailed study to investigate the impact of these structures on the dispersion of air pollution. The study utilized CFD modelling and wind tunnel experiments to assess how the presence of tall buildings affects air pollution dispersion in their vicinity.

The results of the study revealed that high-rise buildings can affect air flow patterns, leading to the formation of "dead-zones" and "hotspots" of high pollution concentration. These areas did not exist prior to the introduction of the tall buildings. The complex CFD modelling provided valuable information for urban planners, allowing them to test different design options against environmental quality criteria.

The height of tall buildings surrounding a "source" building influences the location and extent of newly formed concentration hotspots. Additionally, the interaction between air pollutants and tall buildings can be complex and influenced by various factors, including meteorological conditions such as wind speed and wind direction.

The presence of tall buildings can also trigger the "canyon effect," where air pollutants are trapped and recirculated between the buildings. This increases the exposure time of the pollutants to the buildings, resulting in greater damage to building materials.

Weatherizing buildings without proper ventilation can negatively affect indoor air quality

Weatherizing buildings is a common practice to offset outdoor temperature changes and save energy by reducing the need for heating and cooling systems. However, if proper ventilation is not maintained, it can negatively impact the indoor air quality. Here are some ways in which weatherizing buildings without proper ventilation can affect indoor air quality:

• Increased indoor pollutant levels: Weatherizing buildings creates airtight spaces that can trap pollutants such as combustion gases, secondhand smoke, and volatile organic compounds (VOCs) used in building materials and consumer products. Inadequate ventilation can lead to a buildup of these pollutants, posing health risks to occupants.
• Moisture accumulation and mould growth: Everyday activities like cooking, showering, and hanging wet laundry increase the relative humidity indoors. Without proper ventilation, the high humidity provides an ideal environment for mould, mites, and bacteria to thrive. Mould growth can lead to respiratory problems such as asthma and allergies.
• Poor ventilation and increased exposure to pollutants: Proper ventilation involves exchanging indoor air with fresh outdoor air to dilute and remove pollutant concentrations. Weatherizing without ventilation can result in increased exposure to pollutants, including VOCs, which can have negative health effects.
• Chemical products usage: If mould, bacteria, or pest infestations increase due to higher humidity levels or outdoor temperature changes, people may resort to using chemical products to combat these issues. These chemical products can introduce additional indoor air pollutants if not properly ventilated.
• Health risks: The consequences of poor indoor air quality can range from immediate effects such as eye, nose, and throat irritation, headaches, dizziness, and fatigue to more severe long-term health issues like respiratory diseases, heart disease, and cancer.

To mitigate these negative impacts, it is crucial to prioritize proper ventilation alongside weatherization efforts. This can be achieved through incentives for energy upgrades, establishing minimum "do no harm" measures, and investing in professional training and certification to ensure indoor air quality is maintained while weatherizing buildings.

Burning fossil fuels to power buildings can impact indoor and outdoor air quality

Burning fossil fuels to power buildings can have a significant impact on both indoor and outdoor air quality, with a range of consequences for human health and the environment. Fossil fuels, such as coal, oil, and natural gas, are burned to generate electricity and power buildings. While this has been a common practice for centuries, it comes at a cost to the environment and public health.

Outdoor air pollution from buildings is a pressing issue, as it releases harmful pollutants that affect air quality. One of the most concerning pollutants is particulate matter (PM2.5), which is extremely fine and can penetrate deep into the lungs and even the bloodstream. The burning of fossil fuels also emits nitrogen oxides, which contribute to smog and acid rain formation. These compounds, along with sulfur dioxide and volatile organic compounds, are released into the atmosphere, impacting air quality and public health.

Buildings are significant contributors to outdoor air pollution, especially through the burning of fuels such as gas, oil, biomass, and wood. This has severe health implications, including respiratory issues, cancer, heart disease, and premature death. The impact of building emissions varies across states, with some, like New York and California, bearing a substantial burden. However, it is important to recognize that all states are affected by building pollution, underscoring the need to address this issue.

Indoor air quality is also influenced by the burning of fossil fuels. Emissions released indoors, such as sulfur dioxide, nitrogen dioxide, and carbon monoxide, can directly impact lung health and contribute to ground-level ozone and fine particle air pollution. Even the burning of wood, a traditional source of heat, produces gases known to cause cancer. Additionally, indoor sources of pollution, while contributing less nationwide compared to electric utilities and transportation, can still be significant at a neighborhood level.

Transitioning to cleaner sources of energy is essential to mitigate the impact of burning fossil fuels on air quality. This includes adopting renewable energy sources like solar, wind, and water power, as well as moving towards more efficient electric appliances such as heat pumps and induction stoves, which can help reduce indoor air pollution and improve health outcomes.

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