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A Better Software Option for TANKS 4.09d Emissions Calculations

Historically, industrial sources have relied upon the U.S. EPA's TANKS 4.09d for calculating air emissions from chemical and petroleum storage tanks. Over the years, several errors and calculation mistakes have been discovered and corrected. Eventually, the USEPA elected to stop supporting the software. However, due to lacking an alternative, users had little choice but to use the EPA software to estimate air emissions and state agencies had little choice but to accept these estimates, despite the problems with TANKS 4.09d. The most recent issue with TANKS is that the software will not run on the Windows 10 operating system.

To solve this problem, CFR Environmental created a workbook- based software program that calculates storage tank air emissions per AP-42 Chapter 7.1 exactly. The CFR-E tool is used for all tank types, including vertical fixed roof, internal floating roof, horizontal, external floating roof, and domed external floating roof tanks. The software not only calculates working and breathing losses but it also calculates floating roof landing losses, a feature that is sorely lacking in TANKS. The software includes a library of over than 1,000 petroleum and chemical products with an additional 30,000 compounds that can be added per the users specific request. Input screens mirror TANKS so users can begin using the software immediately. And because the software is workbook based, users can integrate the calculation software into a company’s existing air emission inventory workbooks.

Contact CFR Environmental ( for a free 3-day trial to test drive the newest and best way to calculate storage tank emissions emissions.

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