A standard for measurement of the ability of a translucent panel to obstruct view of objects on the other side from the viewer.
The reason the focus here is on the scattering aspect is due to the fact that achieving privacy through low transmission or high reflectivity depends on lighting conditions and is therefore not intrinsic to the studied material. In the case of a window to the outside, external lighting conditions cannot be controlled, so low transmission/high reflectivity based privacy would only work during the day. While this might be acceptable for commercial buildings with little use at night, or cars where lights are rarely on inside the cabin, it is not acceptable to typical homeowners.
There are several methods by which a panel may obstruct view of an object on one side of the panel from a viewer on the other side. The panel may be opaque. It may redirect light on a large scale to provide a warped image. It may provide surface reflection (as in a one-way mirror). This scope of this standard is limited to a privacy metric for panels that redirect light by scattering to obstruct view via translucency.
Keywords
privacy, translucency, obscurance
Rationale
Privacy glass is an important product, and there are multiple ways that the amount of privacy has been gauged. It would be a service to the industry so customers can compare privacy panels.
