How can the orientation of a blueprint be identified?

The identification of a blueprint's orientation is most effectively done by using a label that specifies "North" or through the inclusion of a compass rose. This designation provides a clear reference point for reading the drawing, allowing anyone reviewing the blueprint to understand which direction is considered 'up' on the plan.

Including a compass rose not only indicates north but can also provide a sense of the scale and layout relative to the actual site or surrounding structures, which is essential in construction and design. While other methods like color coding, title blocks, or grid layouts may provide useful information about the blueprint, they do not specifically address orientation in the way that a north designation or compass rose does. Therefore, understanding how orientation is marked directly affects the capability to interpret the blueprint accurately.