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NIST Standard Reference Database 73

REFLEAK: NIST Leak/Recharge Simulation Program for Refrigerant Blends

Version 5.1

Price: $190.00 PLACE ORDER 

Upgrade: $100.00 ORDER UPGRADE

Purchasers of Version 5.0 can obtain Version 5.1 free of charge

There will be a minimum $30.00 shipping charge for all international shipments of databases via UPS International. Customer will be responsible for their own duties, tax, and VAT. (844) 374-0183 (Toll Free) or data [at] if you have questions.

REFLEAK estimates composition changes of zeotropic mixtures in leak and recharge processes. The leak/recharge simulation program consists of three parts: 1) the pre-processing section for inputting required data, 2) the computation section which simulates leak/recharge processes, and,3) the post-processing section to display calculated results and to print or store data and graphs.

REFLEAK offers the following:

·  Choice of simulation mode between leak only and leak/recharge
·  Choice of process between isothermal (slow) and adiabatic (fast) leak conditions
·  Choice of vapor leak or liquid leak
·  Choice of 69 refrigerants
·  Choice of any mixture, up to 10 components, comprising the above refrigerants
·  Choice of 104 predefined refrigerant mixtures
·  Choice of specifying the initial temperature and initial volumetric quality of charge directly or through specifying the maximum liquid fill at a different fill temperature. The second option is consistent with the specification of the initial    volumetric quality used in ANSI/ASHRAE Standard 34, "Designation and Safety Classification of Refrigerants".
· Choice of specifying the number of recharges, up to 10, and the % mass leaked after each.

Calculated vapor and liquid compositions are displayed in a graphic format. Additional tabular data includes temperature, pressure, volumetric quality, liquid specific volume and vapor specific volume for each 1% of mass leaked throughout the process. Output data can be saved and printed. Thermodynamic properties of refrigerant mixtures are calculated based upon the widely used NIST Standard Reference Database 23 - NIST Reference Fluid Thermodynamic and Transport Properties Database: REFPROP Version 9.1. A user manual and help section is included.

Compared to Version 4.0, this version of REFLEAK uses the representation of thermodynamic properties based on NIST Standard Reference Database 23 - NIST Reference Fluid Thermodynamic and Transport Properties Database: REFPROP Version 9.1 (versus Version 9.0 in REFLEAK 4.0), includes extended list of refrigerants and refrigerant mixtures, and is compatible with the Microsoft® Windows® 7 operating system.

System Requirements: Free space for complete installation: 10 MB. REFLEAK is designed to run on any personal computer (PC) capable of running Microsoft® Windows® 7, 8, and 10 systems.

The installation module requires .NET Framework 4.5.1 (or later version), which can be downloaded from the Microsoft website if not present on the user's PC.

Please click here to view the PDF version of Users' Guide Releak to see how this database works.

For more information, please contact:
Office of Data and Informatics (ODI)
National Institute of Standards and Technology
100 Bureau Dr., Stop 6410
Gaithersburg, MD 20899-6410
(844) 374-0183 (Toll Free) data [at] (E-MAIL)

The scientific contact for this database is:
Piotr A. Domanski
National Institute of Standards and Technology
Engineering Laboratory
100 Bureau Dr., Stop 8631
Gaithersburg, MD 20899 (301) 975-5877 pdomanski [at]

Keywords: Chemical leak; fractionation; recharge; refrigerant; thermodynamic properties; zeotropic mixtures; NIST.

Customer Support


Standard Reference Data, NIST:
100 Bureau Drive, Stop 6410
Gaithersburg, MD 20899-6410
Tel: 844-374-0183 (Toll Free)

If you have any questions regarding this website, or notice any problems or inaccurate information, please contact the webmaster by sending e-mail to: data [at]

Created August 27, 2010, Updated January 28, 2019