Airxchange Inc., the Rockland, Mass.-based manufacturer of energy-recovery-ventilation (ERV) components, recently announced the release of AIRX Estimator for the Environment, a free online tool designed to quickly calculate the energy savings and environmental impact possible when ERV technology is utilized in commercial buildings.

AIRX Estimator for the Environment quickly quantifies carbon-dioxide reduction by energy source using three pieces of information:

• City (currently available for the United States and Canada only).

• The number of hours the building is occupied.

• Outdoor-airflow rate (cubic feet per minute).

If outdoor-airflow rate is not known, AIRX will estimate one based on ASHRAE standards.

Airxchange also provides AIRX calculators for direct-expansion, central-plant, and electric heat systems. They are available at