Automation of Water Resource Recovery Facilities. Water Environment Federation

8.0 REFERENCES

       9.0 SUGGESTED READINGS

1.0 RELATIONSHIP OF SPECIFICATIONS AND DRAWINGS

      The scope of this chapter is limited to discussion of technical requirements for process control systems. Readers are referred to other resources such as the Construction Specifications Institute (CSI) and Engineers Joint Council Development Council for commercial requirements including the bid form, contract terms and conditions, and payment provisions.

      Drawings and specifications work together to establish the requirements of a project, or process control system, which is the term used in this discussion. Typically, text-based requirements in specifications will contain greater detail than drawings because of space constraints in drawings. Information that can be provided pictorially is shown on the drawings, while the details are provided in text-based form. Therefore, each instrument shown on a plan view and each device shown on a network configuration or identified on a schedule should have a corresponding detailed specification. Technical and performance requirements for the instruments or devices should be detailed in the specifications.

      The intended end user of specifications varies. The audience may be the installer (a contractor), financial authority, manager, or equipment operator. Clear presentation of device requirements enables the varied users to better understand the operation or features of the device in advance.

      All steps required for specifying, procuring, installing, and commissioning a complete process control system should be included in the specification process. This consists of specifications and drawings, bidding information, contract terms and conditions, and payment provisions. Inclusion of the phrase, “or equal”, with respect to specific products or manufacturers, may be required to meet competitive bidding requirements. Use of the phrase, “or engineer-approved equal”, may allow the engineer to retain responsibility for determining if the contractor-proposed product meets project specifications while retaining a competitive bid. Correct and detailed process control system specifications are critical to the success of the project. Specifications should include detailed hardware and software requirements, input/output (I/O) signal listings, and control narratives that provide information to the contractor on how to configure control system software to meet project goals.

      In addition to relying on their own experience, design engineers typically rely on the following two key guides when developing detailed specifications: The Project Resource Manual, published by CSI (2005), and Specification Forms for Process Measurement and Control Instruments, Primary Elements and Control Valves (Standard S20) (ISA, 1981). The Project Resource Manual is a master specification document intended to provide every content-related detail that design engineers would need to specify a process control system. Specification forms provide a consistent method of promoting and documenting requirements.

2.0 SPECIFICATIONS

      2.1 Standard Specifications

      Using standard specifications increases the predictability of results for projects with similar content and reduces engineering costs. If engineers wrote requirements for each project without using standard specifications, engineering costs would be significant and project requirements could lack the full documentation necessary for a successful project. The history of multiple projects reflected in standard specifications benefits the project by demonstrating either the completeness or inadequacy of previous specifications. When standard specifications are implemented and revised based on lessons learned, the repeat application increases the predictable outcome of the project. Standard specifications have typically received previous quality reviews for content and format.

2.2 Project-Specific Specifications

      In the event standard specifications are not available for a device or specific application, project-specific specifications will need to be developed. These project-specific specifications may be required for products or applications that are infrequently applied or for new technology. Care should be used to verify the completeness of new or project-specific specifications.

2.3 Vendor-Supplied and -Suggested Specifications

      Documents that itemize technical performance of equipment from the manufacturer are an excellent reference for developing specifications. Edits to specifications suggested by manufacturers may limit competition by incorporating limiting phrases, and the reader is cautioned to understand which phrases are necessary for device selection for project implementation and which phrases effectively reduce competition without project benefit.

2.4 Master Specification Guidelines

      Logically organized specifications allow the reader to find information they need. A standard industry method of organizing specifications available to design engineers is CSI’s “MasterFormat”. MasterFormat includes content, organization, and section numbering of the specification. The CSI created a numbering sequence in 1995 called “MasterFormat 1995”, which created 16 divisions for technical specifications. The organization was revised in 2004 to align more closely with architectural organization format, and a new numbering sequence was established with 44 divisions. Organization of the 1995 specification was not revised in the numbering change implemented in 2004. The CSI format consists of the following three specification topics: general, products, and execution. MasterFormat provides a consistent document form for owners, engineers, and contractors to locate project information. The CSI format continues to evolve and has been republished as “MasterFormat 2010” with additional divisions.

      The CSI manual of practice originally developed in 1948 is a construction industry standard used by professionals to improve and organize construction documents, including project manuals, product data, and cost estimates. The CSI’s primary focus has been on information classification and format of presentation. Format documents (i.e., MasterFormat™, UniFormat™, SectionFormat™, and PageFormat™) and principles outlined in The Project Resource Manual (CSI, 2005) are the results of this classification. The CSI continues to be vital to the construction industry by remaining committed to the maintenance and ongoing improvement of standards to meet the changing needs of the construction industry. The CSI is supported through license fees for their documents.

      The “general” section (Part I) of the specification consists of the following:

      • An outline of the overall work and requirements for equipment and services to be provided;

      • Related work or requirements specified elsewhere; for example, supervisory control and data acquisition (SCADA) system components may be furnished from multiple specification sections, including packaged systems. A transmitter may be supplied by one party, mechanically installed by a second, and electrically wired by a third. References to related work help describe the equipment’s final installed condition;

      • Submittal requirement from the contractor, including

       Bill of materials;

       Manufacturers’ catalog sheets;

       Manufacturers’ data sheets showing options selected and calibration data;

       Loop diagrams showing each loop, with all terminations identified (ISA, 1991);

       Wiring schematics with point-to-point wiring tables and diagrams;