Red Seal Glazier Practice Exam

The term "glass mullion" refers specifically to a structural element that serves as a support for multiple panes of glass, whether arranged vertically or horizontally. Mullions are critical in maintaining the integrity and stability of large glass installations, such as curtain walls or windows. They can help bear the weight of the glass and also provide necessary separation or division between the panes, enhancing the overall structural performance. This understanding of a mullion is essential, especially for glaziers working on large projects, as it relates to both safety and aesthetic considerations in building design.

In contrast, other options refer to different concepts. A decorative element on a glass frame does not contribute to structural support and thus does not define a mullion. Safety glass refers to a category of glass designed to minimize injury during breakage, which is unrelated to the concept of structural support. A tool used in glass cutting is also distinctly different, focusing on the process of shaping or dividing glass rather than supporting it.