V&C Environment Consultants Pty Ltd
- Environmental consulting services based in Melbourne Australia - Service include ISO 14001 development, EMS and risk auditing, training, licence applications and air dispersion modelling.
- http://members.ozemail.com.au/~vcec/

Minnich and Scotto, Inc.
- Scientifically based, environmental consulting firm, provides specialized air quality and meteorological services to industry and government.
- http://www.msiair.net/

Liaise Environmental, Inc.
- Environmental consulting firm specializing in air quality and regulatory compliance
- http://www.liaise.org

Wondermakers Environmental
- Provides consulting and training services relating to air quality assessments. Also provides air and asbestos sampling equipment.
- http://www.wondermakers.com

AmTest Air Quality, LLC
- Provider of comprehensive air pollution testing services to industrial clients.
- http://www.amtestairquality.com/

Environmental Consulting Services
- Consultancy specialising in environmental management systems, emission monitoring, training, support, analytical services and health and safety.
- http://www.halcyon-env.u-net.com/

Beaulier Dust Control
- Consulting engineers in ventilation, dust control and pneumatic conveyor in various industrial sectors, including metallurgy, chemical, plasturgy, mining, transformation, wood and forest.
- http://www.beaulier.qc.ca/

Emission Technologies
- Offers air quality testing and emissions monitoring, modeling, and permitting. Based in the U.S.
- http://www.stacktester.com/

Air Quality Consultants, Ltd
- Offering air quality services for local authorities, developers, and industry, mainly in the UK. Expert witness at public inquiries. Bristol, England.
- http://www.aqconsultants.co.uk

Trinity Consultants
- Offers consulting, software, and training in air quality, including dispersion modeling, permitting, and compliance assessments. Dallas, Texas.
- http://www.trinityconsultants.com

Entech Northwest
- Entech Northwest specializes in air quality consulting, environmental assessment solutions and management for air pollution and noise issues for the transportation and manufacturing sectors.
- http://www.entechnorthwest.com

CETCON (Combustion and Environmental Testing Consultants
- Comprehensive environmental source emission testing services for the gas processing, petrochemical, electric utility, pulp and paper, and general manufacturing industries. Tulsa, Oklhahoma.
- http://cetconinc.com

Air Compliance Testing, Inc.
- Stack testing (EPA industrial air pollution testing), OSHA air compliance monitoring (Industrial Hygiene testing).
- http://www.aircomp.com

Northern Environmental and Monitoring Services (NEMS)
- An environmental consultancy providing specialist services to industry including air quality and stack emission monitoring, contaminated land surveys, noise assessment, environmental impact assessment and ISO14000 management systems and audits.
- http://www.n-e-m-s.com/

OdourNet
- An international group of environmental consultants dedicated to the specialist field of odour assessment, advice on managing odour annoyance and odour abatement.
- http://www.odournet.com/

M.J. Bradley & Associates
- A strategic environmental consulting firm dedicated to air quality issues, energy policy, climate change, electric vehicles, renewable energy, fuel cells and emission credit management.
- http://www.mjbradley.com/

Air Resource Specialists, Inc.
- Provides air pollution monitoring and consulting services for industry and government.
- http://www.air-resource.com/

ARI Environmental Inc.
- ARI provides expert air testing services for industrial clients in the US and Canada. Stack and fugitive emissions testing and consulting since 1980. Offices in Houston, TX, New Orleans, LA and Chicago, IL.
- http://www.arienv.com/

Atlantic Environmental Inc.
- Environmental testing and consulting company with experts in indoor air quality, ergonomics, industrial hygiene, safety, and environmental property assessments. Offices in New York, Atlanta and Chicago.
- http://www.atlenv.com/

Analytical Testing Consultants Corporation
- Provides quality air testing services and efficient answers to a vast array of air pollution problems.
- http://www.atc-net.net/

RAP Services
- An independent air quality consulting firm which operates, maintains and repairs continuous emissions monitoring (CEM) systems for a variety of industries.
- http://www.cemrepair.com/

Clean Air Engineering
- Environmental engineering, air testing, test equipment rental, EPA testing, stack testing, organics testing and particulate testing company. Strength lies in the synergy that comes from bringing these pieces together into an integrated whole.
- http://www.cleanair.com/

ETS Inc.
- Air quality consulting firm, specializing in air emissions control, measurement, training, design, troubleshooting, and regulatory services. Roanoke, Virginia.
- http://www.etsi-inc.com

AirNova, Inc.
- Services include stack testing, stationary source isokinetic sampling, continuous emission monitoring, compliance permitting, air toxics pollution emission sampling, ambient air quality dispersion modeling.
- http://www.airnova.com

Air Tox Environmental Company
- Offers expert air quality management services, continuous emission monitoring, and regulatory compliance support in the United States. Based in Connecticut.
- http://www.airtoxenviro.com/