RED Calc Free

v1.0, Legacy Tool

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You can use RED Calc Pro for 30 days free!

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Summary: This tool, along with a cardboard box and a digital manometer, allows you to accurately measure exhaust airflow at a grille. This custom-made airflow measurement device can be made on site to accommodate tight fitting spaces or exhaust fan grilles that are too large for other measurement methods. See Tool Guide. Click on any input or result label for help. By using this tool (application) you agree to the Terms of Use.

This legacy tool is NOT optimized for mobile devices. Stay tuned for the mobile-optimized version 2.0.