See also:

• Science: Chemistry: Environmental Chemistry: Products and Services: Testing Services  (65)
• Science: Environment: Hazardous Waste: Products and Services: Management, Remediation, and Response Services  (45)

• ActiveSET.org - Directory of stack monitoring firms in Canada and the USA.
• Chester LabNet - Offers inorganic analysis of air samples, including source emissions, ambient and indoor air, with filters available for personal use. Lists methods, and customer services available in Tigard, Oregon.