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Information about Specifications

“Specification” redirects here. For other uses, see Specification (disambiguation).
A specification is an explicit set of requirements to be satisfied by a material, product, or service. (ASTM definition)

Use of a Specification

In engineering, manufacturing, and business, it is vital for suppliers, purchasers, and users of materials, products, or services to understand and agree upon all requirements. A specification is a type of a standard which is often referenced by a contract or procurement document. It provides the necessary details about the specific requirements.

Specifications may be written by government agencies, standards organizations (ASTM, ISO, CEN, etc), trade associations, corporations, and others.

A product specification does not necessarily prove the product to be correct. Just because an item is stamped with a specificaiton number does not, by itself, indicate that the item is fit for any particular use. The people who use the item (engineers, trade unions, etc) or specify the item (building codes, government, industry, etc) have the responsibility to consider the available specifications, specify the correct one, enforce compliance, and use the item correctly. Validation of suitability is necessary.

An example of a US Federal specification is FIPS-PUB 159, Detail Specification for 62.5-μm Core Diameter/125-μm Cladding Diameter Class Ia Multimode Optical Fibers. (Source: from Federal Standard 1037C and from MIL-STD-188)

Content of a Specification

A specification might include:
  • Descriptive title and scope of the specification
  • Date of last effective revision and revision designation
  • Person, office, or agency responsible for questions on the specification, updates, and deviations.
  • The significance or importance of the specification and its intended use.
  • Terminology and definitions to clarify the meanings of the specification
  • Test methods for measuring all specified characteristics
  • Material requirements: physical, mechanical, electrical, chemical, etc. Targets and tolerances.
  • Performance requirements. Targets and tolerances.
  • Workmanship
  • Certifications required.
  • Safety considerations and requirements
  • Environmental considerations and requirements
  • Quality requirements, Sampling (statistics), inspections, acceptance criteria
  • Person, office, or agency responsible enforcement of the specification.
  • Completion and delivery.
  • Provisions for rejection, reinspection, rehearing, corrective measures
  • etc

Construction specifications in North America

Specifications in North America form part of the contract documents that accompany and govern the construction of a building. The guiding master document is the National MasterFormat. It is a consensus document that is jointly sponsored by two professional organisations: While there is a tendency to believe that "Specs overrule Drawings" in the event of discrepancies between the text document and the drawings. The actual intent is for drawings and specifications to be complimentary with neither taking precedence over the other.

The Specifications fall into 50 "Divisions", or broad categories of work involved in construction. The "Divisions" are subdivided into "Sections", that address specific workscopes. For instance, firestopping is addressed in Section 078400 - Firestopping. It forms part of the Division 7, which is Thermal and Moisture Protection. Division 7 also addresses building envelope and fireproofing work. Each Section is subdivided into three distinct areas: "General", "Products" and "Execution". The National MasterFormat system has been uniformly applied to residential, commercial and much though not all industrial work.

Specifications can be another "performance-based", whereby the specifier restricts the text to stating the performance that must be achieved in each Section of work, or "prescriptive", whereby the specifier indicates specific products, vendors and even contractors that are acceptable for each workscope.

While North American specifications are usually restricted to broad descriptions of the work, European ones can include actual work quantities, including such things as area of drywall to be built in square metres, like a bill of materials. This type of specification is a collaborative effort between a specwriter and a quantity surveyor. This approach is unusual in North America, where each bidder performs his or her own quantity survey on the basis of both drawings and specifications.

Specification writing is a professional trade with its own professional designations, such as "CCS", which means "Certified Construction Specifier". Specwriters can be either employees of or sub-contractors to architects. Specwriters frequently meet with manufacturers of building materials who seek to have their products "specified" on upcoming construction projects so that contractors can include their products in the estimates leading to their proposals.

Process Capability Considerations

A good engineering specification, by itself, does not necessarily imply that all products sold to that specification actually meet the listed targets and tolerances. Actual production of any material, product, or service involves inherent variation of output. With a normal distribution, the tails of production may extend well beyond plus and minus three standard deviarions from the process average.

The process capability of materials and products needs to be compatible with the specified engineering tolerances. Process controls must be in place and an effective Quality management system, such as Total Quality Management, needs to keep actual production within the desired tolerances.

Effective enforcement of a specification is necessary for it to be useful.

Software development

Formal specification

Main article: Formal specification
A formal specification is a mathematical description of software or hardware that may be used to develop an implementation. It describes what the system should do, not (necessarily) how the system should do it. Given such a specification, it is possible to use formal verification techniques to demonstrate that a candidate system design is correct with respect to the specification. This has the advantage that incorrect candidate system designs can be revised before a major investment has been made in actually implementing the design. An alternative approach is to use provably correct refinement steps to transform a specification into a design, and ultimately into an actual implementation, that is correct by construction.

Program specification

Main article: Program specification
A program specification is the definition of what a computer program is expected to do. It can be informal, in which case it can be considered as a blueprint or user manual from a developer point of view, or formal, in which case it has a definite meaning defined in mathematical or programmatic terms. In practice, most successful specifications are written to understand and fine-tune applications that were already well-developed, although safety-critical software systems are often carefully specified prior to application development. Specifications are most important for external interfaces that must remain stable.

Functional specification

Main article: Functional specification
In software development, a functional specification (also, functional spec or specs or functional specifications document (FSD)) is the set of documentation that describes the behavior of a computer program or larger software system. The documentation typically describes various inputs that can be provided to the software system and how the system responds to those inputs.

See also

External links

References

  • Pyzdek, T, "Quality Engineering Handbook", 2003, ISBN 0824746147
  • Godfrey, A. B., "Juran's Quality Handbook", 1999, ISBN 007034003
  • "Specifications for the Chemical And Process Industries", 1996, ASQ Quality Press, ISBN:0-87389-351-4
Specification may refer to several different concepts:
  • Specification (technical standard) - an explicit set of requirements
  • Specification (legal concept) - a legal concept of Roman Law

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Engineering is the applied science of acquiring and applying knowledge to design, analysis, and/or construction of works for practical purposes. The American Engineers' Council for Professional Development, also known as ECPD,[1] (later ABET [2]
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Manufacturing (from Latin manu factura, "making by hand") is the use of tools and labor to make things for use or sale. The term may refer to a vast range of human activity, from handicraft to high tech, but is most commonly applied to industrial production, in which raw
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Business law
Business organizations
Basic forms:
Sole proprietorship
Corporation
Partnership
(General · Limited · LLP)
Cooperative
USA:
Business trust · LLC · LLLP
Delaware corporation
Nevada corporation
UK/Commonwealth:
Limited company
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Contract Law
Part of the common law series
Contract
Contract formation
Offer and acceptance  · Mailbox rule
Mirror image rule  · Invitation to treat
Firm offer  · Consideration
Defenses against formation
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CEN can stand for:
  • Cen - the constellation Centaurus
  • Cen, or sen, is the currency of the fictional nation of Amestris of the anime/manga "Fullmetal Alchemist"
  • CEN - the European Committee for Standardization (Comitée Européen de Normalisation)

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The word validation has several uses:
  • In general, validation is the process of checking if something satisfies a certain criterion. Examples would include checking if a statement is true (validity), if an appliance works as intended, if a computer system is secure, or if

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Core Diameter can be defined as in the cross section of a realizable optical fiber, ideally circular, but assumed to a first approximation to be elliptical, the average of the diameters of the smallest circle that can be circumscribed about the core-cladding boundary, and the
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Federal Standard 1037C, entitled Telecommunications: Glossary of Telecommunication Terms is a United States Federal Standard, issued by the General Services Administration pursuant to the Federal Property and Administrative Services Act of 1949, as amended.
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MIL-STD-188 is a series of U.S. military standards relating to telecommunications.

Purpose

Faced with “past technical deficiencies in telecommunications systems and equipment and software…that were traced to basic inadequacies in the application of
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A test method is a definitive procedure that produces a test result. (ASTM definition)

The test result can be qualititive (yes/no), categorical, or quantititive (a measured value). It can be a personal observation or the output of a precision instrument.
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In engineering, tolerance is the permissible limit of variation in 1) a physical dimension, 2) a measured value or property of a material, manufactured object, system, or service, or 3) other measured values (such as temperature, humidity, etc).
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In engineering, tolerance is the permissible limit of variation in 1) a physical dimension, 2) a measured value or property of a material, manufactured object, system, or service, or 3) other measured values (such as temperature, humidity, etc).
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Safety is the state of being "safe" (from French sauf), the condition of being protected against physical, social, spiritual, financial, political, emotional, occupational, psychological, educational or other types or consequences of failure, damage, error, accidents, harm
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natural environment, commonly referred to simply as the environment, is a term that comprises all living and non-living things that occur naturally on Earth or some part of it (e.g. the natural environment in a country).
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Quality in everyday life and business, engineering and manufacturing has a pragmatic interpretation as the non-inferiority, superiority or usefulness of something. This is the most common interpretation of the term.
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Sampling is that part of statistical practice concerned with the selection of individual observations intended to yield some knowledge about a population of concern, especially for the purposes of statistical inference.
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North America is a continent [1] in the Earth's northern hemisphere and (chiefly) western hemisphere. It is bordered on the north by the Arctic Ocean, on the east by the North Atlantic Ocean, on the southeast by the Caribbean Sea, and on the south and west
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building may refer to one of the following:
  1. Any man-made structure used or intended for supporting or sheltering any use or continuous occupancy, or
  2. An act of construction.

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firestop is a passive fire protection system of various components used to seal openings in fire-resistance rated wall and/or floor assemblies through bounding, which is based on elaborate fire testing as well as environmental testing, in some cases.
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A building envelope is the separation between the interior and the exterior environments of a building. It serves as the outer shell to protect the indoor environment as well as to facilitate its climate control.
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Fireproofing on board a ship. The fireproofing consists of a mixture of rockwool fibres with cement and common concrete addmixtures. "Tamping" means that after the spraying, the fresh fibrous spray was flattened down.
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MasterFormat is the most widely used standard for organizing specifications and other written information for commercial and institutional building projects in the U.S. and Canada.
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Europe is one of the seven traditional continents of the Earth. Physically and geologically, Europe is the westernmost peninsula of Eurasia, west of Asia. Europe is bounded to the north by the Arctic Ocean, to the west by the Atlantic Ocean, to the south by the Mediterranean Sea,
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Area is a physical quantity expressing the size of a part of a surface. The term Surface area is the summation of the areas of the exposed sides of an object.

Units

Units for measuring surface area include:
square metre = SI derived unit

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worldwide view of the subject.
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For the musical group "Drywall," see Drywall (musical project)


Drywall, also commonly known as gypsum board,
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A Quantity Surveyor (QS) is a professional person working within the construction industry. The role of the QS is, in general terms, to manage and control costs within construction projects and may involve the use of a range of management procedures and technical tools to achieve
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An architect is a person who is involved in the planning, designing and oversight of a building's construction. The word "architect" (Latin: architectus) derives from the Greek arkhitekton (arkhi (chief) + tekton (builder))")[1]
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Building material is any material which is used for a construction purpose. Just about every type of available material has been used at one time or another for creating various human and animal homes, structures, and technologies.
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normal distribution, also called the Gaussian distribution, is an important family of continuous probability distributions, applicable in many fields. Each member of the family may be defined by two parameters, location and scale: the mean ("average",
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