Blueprint Standards 5
Multicolor Offset Prints.
Sometimes prints are produced in several colors (usually blue and red) via offset printing. Typically the
original drawings are made in smaller scales and sizes for further economy. The various colors are used
to highlight new work in relation to existing construction or to display complex mechanical or electrical
systems in new projects. The main advantage to the use of colors is in facilitating the reading of the
drawings, resulting in fewer mistakes and requiring less time in interpreting them.
More recently, designs created using computer-aided-design techniques may be transferred as a
digital file directly to a computer printer or plotter; in some applications paper is avoided altogether and
work and analysis are done directly from digital displays. Even as print and display technology ad-
vances, the traditional term "blueprint" continues to be used informally to refer to each type of image.
Computer-Aided Design and Drafting.
Computer-aided design (CAD) has brought a new innovation to the field of engineering design and is
discussed in greater detail in Chapter 2. CAD is used to design, develop, and optimize the process to
make a clean, clear, computer-generated construction drawing, accurately drafted as per specified di-
mensions. CAD has turned out to be an invaluable technology with great benefits, such as lower prod-
uct-development costs, faster processing, and a greatly shortened design cycle. It is a technology that
permits the consultant to focus on the business of design instead of wasting time searching for and re-
drawing old documents.
CAD drawings can be generated from most formats including hand-drawn documents, tiff files, or
any other image files that can be converted to a .dwg file using AutoCAD or other CAD software.
1.3 BASIC DRAFTING STANDARDS AND STANDARDS-SETTING ORGANIZATIONS.
In the United States, the American National Standards Institute (ANSI) and the International Organiza-
tion for Standardization (ISO) have adopted drafting standards that are voluntarily accepted and widely
used throughout the world. These standards incorporate and complement other architectural/engineer-
ing standards developed and accepted by professional organizations such as the American Institute of
Architects (AIA), the American Society of Mechanical Engineers (ASME) and others. Some large firms
have adopted their own standards to suit their individual needs.
ANSI Standards for Blueprint Sheets.
Most architectural-drafting offices in the United States use ANSI standard sheet sizes as shown in Table
1.1. ANSI Y14.2, Y14.3, and Y14.5 are the standards that are commonly used in the U.S.:
- In the U.S. letter-size paper is an architectural (first series) A-size sheet. It is 8.5 11 inches. An
engineer’s (second series) A-size sheet is 9 12 inches. - B-size sheets are double the size of A sheets (11 17—also called tabloid—or 12 18 inches).
- C-size sheets are double the size of B sheets (17 22 or 18 24 inches).
- D-size sheets are double the size of C sheets (22 34 or 24 36 inches), and so on.