Frequently Asked Questions

This is a sidebar to the article A Manufacturer's Guide to IG Certification.


What is ASTM E 2190?
ASTM E 2190 was approved in 2002 as part of a continuing effort to harmonize North American standards for IG testing and performance. E 2190 is a standard specification for IG unit performance and evaluation designed to be equal to or improved over its predecessors ASTM E 774 (U.S.) and CGSB 12.8 (Canada).
ASTM E 2190 testing is divided into three parts:

  •  High Humidity Test-IG samples are subjected to two periods of continuous high-humidity and high temperature (95 percent RH at 140¡ F) exposure. The first period is for 28 days prior to Accelerated Weathering testing and the second is for 14 days following weathering.
  • Accelerated Weathering-Testing simulates weather cycling from -20¡F to 140¡F with high humidity and ultraviolet radiation exposure over a 63-day time period.
  • Volatile Fog Test-Uses ultraviolet radiation and elevated temperatures to show whether or not IG units contain volatile components or materials that may condense inside the IG unit as a visible "fog."

Will my single seal system pass ASTM E 2190?
Because of the stringent nature of E 2190 test methods, some units-particularly those with only a single-seal construction-may have difficulty passing the test requirements and some reengineering may be required.

What are the standard sample sizes for IG certification?
14 x 20 inches; 4 mm (5/32-inch) glass with 12mm (1/2-inch) airspace or 5 mm (3/16-inch) glass with 6 mm (1/4-inch) airspace

How many test units are required for IG certification?

Twelve units are required and are dispersed as follows:

  • Six units for the high humidity and accelerated weathering
  • Two units for the volatile fog box
  • Two units to allow for breakage during shipping
  • Two units to allow for breakage during testing


What if my system does not pass ASTM E 2190?
Manufacturers should give themselves plenty of time before the mandate goes into effect and anticipate additional costs to redesign or purchase new IG fabrication equipment necessary for them to be compliant.

Who should I contact to begin the IG certification process?
Upon evaluating your system, contact an IG certification agency (see IG certification agency directory).