Step 1
Place the operating end of an argon analyzer against an argon-filled window's glass. If the window has a low-emissivity (low-e) glass coating, then test the side of the window that isn't coated.
Step 2
Turn on the argon analyzer. The analyzer will measure the amount of argon in the window.
Step 3
Interpret the result that appears on the argon analyzer's display screen. The result probably is a percentage. The ideal percentage of argon in windows for maximum energy efficiency is 90 percent or greater. A window has no or very little argon if the analyzer displays an error message or a very low percentage.