Based in Columbia, Maryland, USA (with other offices in Canada, South America, Europe and Asia), General Physics is a firm of scientists, technologists and engineers whose air emissions management services include air dispersion modeling in support of air emissions compliance studies, offsite consequence analyses, and evaluation/selection of emission stack heights.

A firm located in Chennai, India offering: HAZOP training and software; air dispersion modeling; failure and reliability analysis; risk assessment; and accident investigation ... all targeted for the chemical process industries.

An environmental consulting company based in Texas (with offices in Richardson, Austin and Beaumont)who offer services in air dispersion modeling, air permitting and compliance, risk management plans and offsite consequence analyses.

Earthguard Environmental is a consulting firm (based in Richmond Hill, Ontario, Canada) that provides services for development, evaluation and application of air dispersion models using EPA and other regulatory models as well as specialized models designed for specific applications.

A software development company in Toronto, Canada that also provides a full range of risk management consulting services. They offer software for Risk Analysis, Process Hazard Analysis (PHA), HAZOP, Failure Modes and Effects Analysis (FMEA), and Risk Management Plans (RMP).

An environmental consulting and engineering firm (located in Bloomfield, Connecticut, USA) whose air quality services include air emissions dispersion modeling, accidental release modeling, and cooling tower impact modeling.

An applied research institute located in Bratislavia, Slovak Republic whose services include air dispersion modeling using the CFD program called Fluidyn-PANACHE.

An international firm (headquartered in Houston, Texas, USA) providing engineering, and technological services for analyzing and managing hazards, risk, and safety as well as minimizing environmental impacts. Their air dispersion models, offered from their office in Bethesda, Maryland are for routine and accidental airborne releases. Versions available are: quick-running plume model, urban dispersion model and inside building model.

An engineering, construction and environmental consulting firm based in Nottingham, England with 40 offices in Europe and North America. Their services include air pollution dispersion modeling in support of environmental impact studies as well as response planning for accidental releases.

A consulting engineering firm headquartered in Albuquerque, New Mexico, USA (with multiple offices in the USA and Canada) whose air quality services include air dispersion modeling.