Air Quality

All facilities that release air emissions are required to comply with air quality permitting requirements. Having an up-to-date air permit and remaining in compliance with the permit, including sampling and recordkeeping obligations, is of great importance where air emissions exist. CTI has extensive experience assisting industrial facilities in complying with these comprehensive air quality regulations. Our staff consists of qualified engineers that can help determine what actions are needed in order to obtain and maintain regulatory compliance. CTI’s staff is experienced in communicating with state and federal regulatory agencies, supervising stack and emission tests, preparing all required permit applications, and compiling site-specific recordkeeping programs that are suitable with each client’s personal needs.

Air Quality Permitting

Air permit applications are required for new facilities that emit air pollutants and for modifications and expansions at existing facilities. CTI can determine what type of permit your facility needs and assist with every step of the permitting process. The different types of permits are:

  • Title V Permits
    Applies to new facilities that have the potential to emit air pollutants above the Title V major source thresholds and significant modifications at existing major source facilities.
  • Synthetic Minor/Conditional Major Permits
    Applies to facilities that have the potential to emit air pollutants above the Title V major source thresholds but take restrictions or limits so that the potential to emit is less than the Title V major source thresholds.
  • Minor Permits
    Applies to facilities that have the potential to emit air pollutants below the Title V major source thresholds.
  • Prevention of Significant Deterioration (PSD)
    Applies to facilities that have the potential to emit air pollutants above the PSD major source thresholds. PSD major source thresholds are higher than Title V major source thresholds. PSD facilities must still obtain a Title V permit, but with additional PSD requirements.
  • Nonattainment New Source Review (NNSR)
    Applies to major source facilities or modifications at major source facilities located in a nonattainment area. NNSR facilities must still obtain a Title V permit, but with additional NSSR requirements.

Please refer to the links below for more information on Air Quality Permitting:

EPA New Source Review Permitting:

EPA Title V Permitting:

Air Quality Compliance

After an air permit is issued, facilities must comply with all applicable requirements in the permit for the duration of permit coverage. CTI can help your facility maintain compliance with every aspect of the permit including:

  • Title V, PSD, and NNSR requirements
  • NESHAP/MACT Standards
  • New Source Performance Standards (NSPS)
  • Quarterly/Semiannual Reporting
  • Emission Inventories
  • Emission Fees
  • Emission Testing
  • Recordkeeping
  • Air Pollution Control Evaluation and Design

Air Dispersion Modeling

Air dispersion modeling is often required for new facilities or major projects at existing facilities in order to evaluate the ambient air impacts of the emissions associated with the projects. CTI has the resources and capabilities to conduct the air dispersion modeling required as part of the permitting process or as requested by state or federal regulatory agencies. The two most common types of air quality modeling are toxic air pollutant (TAP) modeling and PSD modeling.

  • TAP Modeling
    Toxic air pollutants are pollutants that are known or suspected to cause cancer, or other serious health effects, or adverse environmental effects. TAP modeling is required for all new facilities that require an air permit and emit TAPs and for existing facilities that add new or modify existing equipment that increases emissions of TAPs. The goal of air dispersion modeling is to demonstrate that emissions of TAPs from the facility will not exceed allowable ambient concentrations which can have significant impacts on ambient air quality standards.
  • PSD Modeling
    Facilities that are subject to PSD regulations are also required to conduct air dispersion modeling. Proposed new PSD major source facilities and major modifications at existing PSD major source facilities must conduct an air quality analysis to demonstrate that emissions from the proposed project will neither cause nor contribute to a violation of the National Ambient Air Quality Standards (NAAQS) or PSD increments (the amount of pollution an area is allowed to increase). Air dispersion modeling for PSD is only required for the following pollutants:

    • PM5
    • PM10
    • SO2
    • NO2
    • Pb
    • CO

For more information about Boiler MACT/GACT Compliance, click here.

Click below to explore the environmental consulting services that CTI offers for any aspect of air, land, and water protection and compliance.


Air Quality
Brownfields Redevelopment
Environmental Compliance Audits
Environmental Management Systems
ISO 14001 Consulting
Phase I & II Environmental Site Assessments
RCRA Compliance
SARA Title III – Tier II / Form R
Spill Prevention Control and Countermeasures (SPCC)
Industrial Stormwater Permitting
Wastewater Permitting and Compliance

Environmental Consulting Services