Understanding VOCs, HAPs, and Emission Regulations.

Volatile Organic Compounds (VOCs) and Hazardous Air Pollutants (HAPs) are released when chemicals vaporize into gas. These pollutants contribute to ground-level smog, posing serious health risks to humans and causing long-term environmental damage. To protect communities and ecosystems, the Environmental Protection Agency (EPA) regulates the amount of VOCs and HAPs that manufacturers can emit.

Different product categories, such as automobile coatings, architectural coatings, and aerosol products, have specific emission guidelines. Consequently, facility owners may face varying restrictions for both production processes and plant emissions.

Federal Regulations

The Clean Air Act of 1970 The Clean Air Act (1970) sets emission limits for stationary and mobile sources. Under this law, the EPA enforces National Volatile Organic Compound Emission Standards to help industries reduce VOC emissions—targeting a reduction of roughly 90,000 tons annually.

Industries must adhere to VOC-to-product ratios to remain compliant. For instance, pretreatment wash primers in automobile coatings must contain no more than 780 grams of VOCs per liter of product. Regulatory limits apply across all manufacturing stages to ensure emissions remain within national thresholds.

Compliance is further monitored through the EPA’s National Emission Standards for Hazardous Air Pollutants (NESHAP) program. Large stationary sources, or “major sources,” undergo performance testing and on-site monitoring every two years to control pollutants linked to severe health risks and birth defects.

State-Level Regulations

The Clean Air Act also requires states to uphold air quality through State Implementation Plans (SIPs), which can impose stricter limits than federal regulations. This means your facility’s location can influence its specific emission requirements.

Manufacturers can meet these limits by reducing VOC usage in production or installing emission control systems to capture or destroy harmful pollutants. Often, a combination of both strategies is necessary. The EPA maintains a database of active SIPs and industry-specific emission limits for each state.

Reasonably Available Control Technology (RACT)

The EPA bases compliance assessments on Reasonably Available Control Technology (RACT), which considers current technological capabilities when setting emission limits. As regulations evolve, technologies are reassessed to ensure standards remain achievable.

Upgrading outdated emission control units not only supports regulatory compliance but can also reduce operational costs and lower overall emissions. Regular maintenance and review of emission control systems are essential to keeping your facility aligned with evolving regulations.

Recent Regulatory Changes

Emission rules are continually updated at both federal and state levels. For example:

  • Maryland and Connecticut recently tightened emission limits for new and existing facilities.
  • California’s 2017 SIP revision introduced reporting requirements for large retailers.

With regulations evolving alongside new technologies and manufacturing processes, manufacturers must stay proactive. Implementing advanced emission control solutions ensures compliance while minimizing environmental impact.

The Importance of an Emissions Control Unit

The type of industry and the chemicals emitted may dictate whether a control system is necessary. For example, the EPA requires automobile coating operations to reduce the use of VOCs in its production process, causing businesses to alter front-end production techniques.

In contrast, chemical manufacturers are required to lower their overall emission levels, placing a focus on waste control. Emission control systems use absorption techniques combined with thermal and catalytic incineration to not only reduce the number of harmful pollutants released into the air but also help manufacturers avoid changing their production process.

Types of Emission Control Systems Available

The following systems are used across applicable industries:

Emission control systems vary in cost, destruction rate, and combustion method. Absorption techniques remove harmless particles from the air and collect them for destruction or redistribution, while combustion systems heat and break down the compounds into harmless particles. Although some units collect but do not destroy VOCs, manufacturers must consider the removal of the remaining pollutants to repurpose, sell, or dispose of them safely.

Narrowing Down Your Options

It’s important to consider the heating methods of each control unit and how they fuel the combustion process. For example, the amount of fuel required to operate thermal oxidation may outweigh the benefits of the system itself. Furthermore, nitrogen oxides (NOx) are produced when combustion occurs, causing a possible increase in the overall emissions output instead of a reduction.

As an alternative, catalytic oxidation requires lower temperatures and therefore produces less NOx. However, the system’s application is limited due to the potential poisons released during operation. The type of VOCs created in production may also influence the type of system required. For example, a cyclone-based filtration system may capture larger particles more efficiently.

When deciding what system to use, consider the utility costs, facility layout, regulatory requirements, and current VOC emission levels. While the operation expenses of a regenerative catalytic oxidizer are low, the system is only suitable for low-VOC outfits. Similarly, the operating costs of a recuperative thermal oxidizer may be higher than others, but the destruction efficiencies can be greater the 99 percent.

Depending on the type of commerce and the facility in question, manufacturers may be able to use the energy released by the production process to fuel the combustion within the control unit itself.