military. A bill of material for an electrical plan is shown in figure 2-4.
Even well-drawn construction drawings cannot adequately reveal all the aspects of a construction project. There are many features that cannot be shown graphically. For instance, how can anybody show on a drawing the quality of workmanship required for the installation of electrical equipment or who is responsible for supplying the materials, except by extensive hand-lettered notes. The standard procedure then is to supplement construction drawings with written descriptions. These detailed written instructions, commonly called specifications (specs), define and limit the materials and fabrication according to the intent of the engineer or the designer. The specifications are an important part of the project because they eliminate possible misinterpretation and ensure positive control of the construction.
There are many different types of specifications. A few of those common to the Naval Construction Force (NCF) will be discussed here.
NAVFACENGCOM specifications are prepared by the Naval Facilities Engineering Command, which sets forth the standards of construction for the NCF and all work performed under the jurisdiction of the Naval Facilities Engineering Command.
Several types of specifications influence the preparation of NCF project specifications. These include NAVFACENGCOM guide specifications and type specifications; commercial specifications and standards; technical society and association standards, such as American National Standards Institute (ANSI) and Underwriters Laboratories (UL); and manufacturers' standards.
Figure 2-4. - Bill of material.Continue Reading