The Iris damper permits airflow to be adjusted and measured at one location, resulting in reduced time and improved accuracy in air balancing, says the company. It has interlocking steel plates and a calibrated control lever to form an adjustable aperture. According to the manufacturer, by measuring differential pressure across the pressure ports and referring to the matching performance curve, airflow can be determined precisely. With capacities to 20,000 cfm, 10 sizes are available, ranging from 4 to 32 inches. It is made of galvanized steel and fitted with a neoprene gasket; stainless steel and motorized version are available.

Continental Fan Manufacturing Inc., 203 Eggert Rd., Buffalo, NY 14215; 800-779-4021; 716-842-0611 (fax);

eProduct #182