Mirrors
Most mirrors are manufactured by the wet chemical deposition method, although a few, for specialized use, are made by vacuum deposition. Safety mirrors are available to meet various laws and building codes. A mirror made from tempered glass will have the inherent distortion from the tempering process and cannot have the same quality in reflection as laminated ones made from mirror quality annealed float glass. Transparent, or two-way mirrors, are designed to allow vision through from one direction while presenting a mirror appearance from the opposite side. Their major application is to permit undetected observation for study or surveillance in places such as prisons, gambling casinos and psychiatric treatment centers. A difference in lighting level is necessary; in the room to be studied the lighting level should be at least five times greater than the lighting level in the observation room; ten times greater is even more effective. Two way mirrors are not intended for use in exterior walls.

Negative Phase
The portion of a blast wave, also known as "suction phase", whose pressure is below ambient.

Pane
A glass-filled division of a window, door or wall, or the glass itself.

Plate Glass
Plate glass, manufactured by the grinding and polishing process, is no longer produced in the United States, and words referring to it have been eliminated from the ASTM Specification C103685. It has been replaced by the float glass process.

Positive Phase
The portion of a blast wave whose pressure is above ambient.