{"id":2217,"date":"2025-06-04T14:15:41","date_gmt":"2025-06-04T14:15:41","guid":{"rendered":"https:\/\/tricordconsulting.com\/?p=2217"},"modified":"2025-06-18T16:04:46","modified_gmt":"2025-06-18T16:04:46","slug":"is-it-time-to-reevaluate-your-storage-tank-calculations","status":"publish","type":"post","link":"https:\/\/tricordconsulting.com\/index.php\/2025\/06\/04\/is-it-time-to-reevaluate-your-storage-tank-calculations\/","title":{"rendered":"Is It Time to Reevaluate Your Storage Tank Calculations?"},"content":{"rendered":"\n
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Storage tank emissions calculations by nature are fairly easy to generate and similarly fairly easy to take for granted. The calculations often remain untouched as methodologies rarely change absent significant updates to Chapter 7, Section 1 (Organic Liquid Storage Tanks) of the USEPA\u2019s AP-42 guidance. While the USEPA made some changes in the latest version of Chapter 7 issued in October of 2024, the last major revision occurred in 2019 and it is likely many sites haven\u2019t given much thought to their tank calculations since that time. However, last year, the USEPA released TANKS 5.1 replacing TANKS4.09 which has been unsupported since 2012. In fact, many agencies ceased allowing the use of TANKS4.09, driving many facilities to explore using third party calculations or to create their own internal tools. With the release of the free-for-use TANKS 5.1 and since we are past the majority of states\u2019 emissions inventory submittal deadlines, now may be a good opportunity to reevaluate your storage tank calculations.<\/p>\n\n\n\n

TANKS 5.1 is a browser-based application built with JavaScript available through the USEPA\u2019s website (https:\/\/www.epa.gov\/air-emissions-factors-and-quantification\/tanks-emissions-estimation-software-version-5<\/a>) that mirrors the current version of Chapter 7.1 of AP-42. The tool will calculate both routine and non-routine for fixed and floating roof tanks, as well as rectangular tanks. It also has the ability to calculate heating cycles, tight-fitting seal losses, and adjusted emissions based on the efficiency of an add-on control device. The application is fairly customizable, allowing the input of custom organic liquids, petroleum liquids, mixtures, and meteorological data.<\/p>\n\n\n\n

However, there are a few items to be aware of before committing to a wholesale switch to TANKS 5.1. A few key points to note are as follows:<\/p>\n\n\n\n