The test data is obtained in accordance with ASTM E595-93 "Total Mass Loss and Collected Volatile Condensable Materials from Outgassing in a Vacuum Environment". The test involves heating a specimen of material to 125°C for 24 hrs while in vacuum. Specimen mass is measured before and after the test to determine total mass loss (TML). A small plate at 25°C is placed in close proximity to the specimen to determine the collected volatile condensable material (CVCM). Thousands of materials of interest to the aerospace community have been tested including potting compounds, foams, elastomers, films, tapes, insulations, shrink tubings, adhesives, coatings, fabrics, tie cords, and lubricants.

The E595 data is most often used as a screening test for spacecraft materials. Actual surface contamination from the outgassing of materials will, of course, vary with environment and quantity of material used. The criteria of TML < 1.0% and CVCM < 0.1% has been typically used to screen materials from an outgassing standpoint in spaceflight applications.

The outgassing database can be accessed from the home page of GSFC's Materials Engineering Branch at http://arioch.gsfc.nasa.gov/313/. Scroll to the bottom of the page and select Outgassing Database.

Tim Van Sant NASA Goddard Space Flight Center Materials Engineering Branch/Code 313 Greenbelt, MD 20771 John.T.VanSant.1@gsfc.nasa.gov (301) 286-6024 fax (301) 286-1646