How are revisions documented on blueprints?

Revisions to blueprints are documented by using revision clouds to highlight the areas that have been changed and providing details in a revision block. This method allows for clear communication regarding what specific parts of the blueprint have been modified. Revision clouds are visually distinct shapes drawn around the changes, making them easy to identify, while the revision block contains information such as the revision number, date, description of the change, and who approved it. This systematic approach ensures that any updates are easily traceable and maintain the clarity and integrity of the blueprint's historical records.