A proposed new standard could assist manufacturers in the selection of glass or glazing with the necessary EMI shielding capability and communication transmittance rate for the application in which it is being used.
International standards organization ASTM International has announced that ASTM WK41897, “Test Method for EMI Transmittance and Shielding Rating for Glazing Infill,” is being developed by Subcommittee F12.10 on Systems Products and Services, part of the ASTM International Committee F12 on Security Systems and Equipment.
According to Julia Schimmelpenningh, global architectural application manager of Eastman Chemical Co. and an F12 member, information can move through glass or glazing with varying degrees of effectiveness as needed, depending on the EM transmittance level of the material. In some cases, she said, a high transmittance rate is desired, such as for cell phone reception or automatic payment systems on a toll road; while a low transmittance rating is preferable in other scenarios, such as in buildings in which sensitive information is housed.
“It has been determined that there is a significant need and desire to create a standardized methodology for acquiring an electromagnetic interference rating for glazing, so that components of the glazing system could be selected based on a level and accepted playing field,” Schimmelpenningh said.
The proposed standard will include a test method by which lites or glazings can be evaluated for their transmittance on, or shielding capability to, electromagnetic frequencies. Use of the test method could help generate data for glazing infill that can be used by consumers, designers and system manufacturers to understand the capability and contribution of glazing materials to EMI security systems, the company said.
“We anticipate that once it has been approved, the proposed standard will be used as a mechanism to aid in the selection of glazing infill materials for the production of windows, doors, skylights, cars, planes, boats and more,” Schimmelpenningh added.
