Engineers' Role In Reducing Air Pollution

Air pollution is a pressing global issue that poses significant risks to human health and the environment. It is caused by a complex mix of chemicals emitted from various sources, including industrial manufacturing, vehicles, and natural occurrences like forest fires. The World Health Organization (WHO) estimates that approximately 4.2 million people die each year due to outdoor air pollution. To combat this, environmental engineers play a crucial role in identifying and addressing air pollution. These engineers specialize in air quality engineering and air pollution control, developing strategies to reduce and prevent the emission of harmful pollutants. They employ their expertise in chemistry, biology, and statistics to model and understand pollution sources, monitor emissions, and design effective solutions. This involves creating control mechanisms, such as ventilation systems and baghouses, to capture and reduce pollutants. Additionally, they work across sectors to enforce compliance with air quality regulations, such as the Clean Air Act, to ensure industries adhere to environmental standards. The work of environmental engineers is vital in mitigating the health, environmental, and economic impacts of air pollution, ultimately striving to improve air quality and protect public health.

Identify and contain key atmospheric pollutants

Air pollution is a pressing issue that poses a threat to both human health and the climate. It is caused by the release of gases, solids, and liquid aerosols into the atmosphere, which exceed the environment's capacity to dissipate, dilute, or absorb them. These pollutants are often released by household combustion devices, motor vehicles, industrial facilities, and forest fires.

To address this issue, air quality engineers play a crucial role in identifying and containing key atmospheric pollutants. Here are some strategies and technologies they employ:

Identifying Pollutants

The first step in containing atmospheric pollutants is to identify the sources and types of pollutants. Air quality engineers study the compounds used in industrial processes and the resulting air pollutants. For example, when a new chemical factory is being constructed, engineers will analyse the types of compounds used and predict the air pollutants that may be generated. This identification process is crucial for devising effective containment strategies.

Regulatory Standards

Various regulatory standards have been established to control common pollutants. The Clean Air Act, enacted in 1970, regulates the amount of pollutants that can be released into the air. The U.S. Environmental Protection Agency (EPA) has designated six common air pollutants as "criteria" pollutants, including particulate matter, ground-level ozone, carbon monoxide, sulfur dioxide, nitrogen dioxide, and lead. These criteria pollutants are useful indicators of overall air quality and have set maximum acceptable concentrations in the atmosphere.

Modelling and Understanding Pollution

Air quality engineers employ modelling and statistical techniques to understand pollution levels and their sources. They use statistical models to link pollution levels to specific fuels, contaminants, and air patterns. This helps in the development of appropriate technologies and regulations to address the pollution. For instance, air quality modelling played a crucial role in reducing nitrogen dioxide levels by 64% between 1980 and 2021.

Compliance and Enforcement

Air quality engineers ensure compliance with federal, state, and local regulations. They review applications for installation permits, assess compliance with the Clean Air Act and other applicable standards, and assist industries in meeting specific compliance standards. This includes working with both the public and private sectors to ensure adherence to environmental regulations.

Designing and Implementing Solutions

Engineers design and implement infrastructure and technologies to reduce and contain atmospheric pollutants. They develop ventilation systems, baghouses for removing particulates, regenerative incinerators for controlling pollution from volatile organic compounds, and other control mechanisms. Additionally, they collaborate with architects and building designers to optimise air quality in new or existing construction projects.

Natural Cleaning Methods

In addition to engineered solutions, nature also plays a role in cleaning the air. Hurricanes, tornadoes, precipitation, plants, and even the mucus inside our noses all contribute to reducing air pollution.

Monitor emissions and ensure compliance with regulations

Air quality engineers are responsible for monitoring emissions and ensuring compliance with regulations. This involves collecting and measuring samples of ambient air pollutants to evaluate the atmosphere's status and ensure it meets clean air standards. They also review applications for installation permits and assess compliance with relevant laws and regulations, such as the Clean Air Act.

In the United States, the Environmental Protection Agency (EPA) plays a crucial role in reducing air pollution. The EPA has implemented stringent emission standards and promoted cleaner-burning gasoline to reduce emissions from vehicles and engines. Additionally, they have addressed indoor air pollution through voluntary programs. The EPA's regulations and standards aim to protect public health and the environment by reducing toxic air pollutants.

One of the key tools for monitoring compliance is the inspection. The EPA conducts inspections by visiting facilities or sites to gather information and determine compliance with environmental regulations. These inspections include activities such as interviewing site representatives, reviewing records and reports, collecting samples, and observing operations. Compliance monitoring also includes formulating and implementing compliance monitoring strategies and providing compliance incentives to encourage facilities to disclose violations.

To ensure compliance with the Clean Air Act, the EPA and state and local air pollution agencies collect national air quality data on criteria pollutants, including carbon monoxide, nitrogen dioxide, ozone, lead, particulate matter, sulfur dioxide, and volatile organic compounds. This data is essential for evaluating the status of the atmosphere and taking necessary actions to improve air quality.

Air quality engineers also play a vital role in monitoring and ensuring compliance. They work with both government agencies and the private sector to ensure adherence to environmental regulations. Their expertise in chemistry, biology, and statistics informs their decisions and helps achieve the ultimate goal of controlling and reducing pollution to improve public health.

Design and implement quality improvement solutions

Designing and implementing quality improvement solutions is a key role for air quality engineers. They must be creative in devising new techniques to prevent air pollution, especially from manufacturing and industrial sources, which are the biggest contributors to poor air quality.

When a new manufacturing plant is being built, environmental engineers will identify the various compounds and pollutants that will be generated during the production process. They will then design and implement control mechanisms to reduce the amount of pollution emitted. This could include recommending the installation of air pollution equipment such as thermal oxidizers, which can destroy high-volume Volatile Organic Compounds (VOCs) and Hazardous Air Pollutants (HAPs). Other measures include complex ventilation systems and baghouses, which are used to remove particulates at steel mills, fossil fuel-burning power plants, and pharmaceutical factories.

Air quality engineers also work to ensure compliance with federal, state, and local regulations, such as the Clean Air Act in the United States, which regulates how much of any pollutant can be released into the air. They may review installation permit applications, assess atmospheric emissions, and enforce standards for controlling emissions.

To improve air quality, engineers may also recommend natural cleaning methods, such as using plants, especially spider plants, which can help to clean the air.

Understand sources of air pollution

Understanding the sources of air pollution is a critical step in devising strategies to mitigate it. Air pollution is caused by a range of sources, both natural and anthropogenic (man-made). Here is a detailed breakdown of the various sources of air pollution:

Natural Sources:

• Forest fires and wildfires: Uncontrolled fires in forests and rural areas can release massive amounts of smoke and pollutants into the atmosphere. These fires are often caused by natural events like lightning strikes.
• Volcanic activity: Volcanic eruptions release ash and gases into the atmosphere, which can lead to air pollution.

Anthropogenic Sources:

• Internal combustion engines: Gas- and diesel-powered vehicles, including cars, trucks, and construction equipment, are significant contributors to air pollution.
• Fossil fuels: The combustion of fossil fuels, such as coal, natural gas, and gasoline, releases pollutants like carbon dioxide, nitrogen oxide, and sulfur dioxide.
• Industrial manufacturing: Factories, refineries, and power plants emit toxic chemicals, including mercury and lead, as well as particulate matter.
• Residential energy use: Household combustion devices, such as burning kerosene, wood, or coal for cooking, heating, and lighting, can release pollutants and contribute to indoor air pollution.
• Agriculture and waste incineration: Agricultural practices and waste incineration processes can release pollutants into the atmosphere, impacting air quality.
• Power generation: The generation of electricity, particularly from fossil fuel power plants, can be a significant source of air pollution.

It is important to note that in large cities, air pollution is often more concentrated due to emissions from multiple sources. Additionally, certain geographical features, such as mountains or tall buildings, can prevent air pollution from dispersing, leading to the formation of smog.

Reduce emissions from vehicles and engines

Choose fuel-efficient vehicles

When shopping for a new car, opt for fuel-efficient vehicles with low greenhouse gas emissions. These cars are environmentally friendly and can also save you money on fuel costs. Examples include plug-in hybrid electric vehicles, hydrogen fuel cell vehicles, and cleaner-burning gasoline vehicles.

Drive efficiently

The way you drive can significantly impact emissions from your vehicle. Here are some tips for more efficient driving:

• Go easy on the gas pedal and brakes.
• Avoid unnecessary idling, especially in cold weather, as modern vehicles do not require "warming up."
• Observe posted speed limits and drive within the speed limit. Driving faster burns more fuel and emits more pollutants.
• Accelerate gradually. Getting a vehicle moving from a complete stop uses the most energy, so anticipate the road ahead and maintain a steady speed.

Maintain your vehicle

Regular maintenance of your vehicle is crucial to ensure it runs as clean and efficiently as possible. Follow the manufacturer's maintenance schedule, use the recommended motor oil, and keep your tires properly inflated. Refer to your owner's manual for specific instructions and guidelines.

Optimise home deliveries

When shopping online or getting home deliveries, consider the following tips:

• Choose longer time windows for deliveries to allow delivery trucks to optimise their routes and avoid unnecessary trips.
• Request all your packages to be sent in one shipment with minimal packaging.
• Opt for online grocery shopping instead of driving to the store.

Use efficient lawn and gardening equipment

Gas-powered engines in lawn and garden equipment contribute significantly to air pollution. Here are some suggestions to reduce their impact:

• For small lawns, use a manual (reel) mower.
• Look for electric and battery-powered machines that are quieter and less polluting than gas-powered alternatives.
• Properly maintain your lawn and garden equipment by tuning mowers and changing the oil regularly.

Frequently asked questions