Quality Specification

8/1/2019 Quality Specification

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Quality Specification



Outline

What is Quality Specification

Importance of SpecsSpecs role in Maintaining Quality

Process of Spec Sheet developmentConcept of Tolerances



SpecificationsA specification, or spec is a precise statement of aset of requirements to be satisfied by a material,product, system, or service that indicates theprocedures for determining whether each of therequirements is satisfied.

Several key elements has to be emphasized in this

definition.



RequirementsRequirements indicate that these expectations arenonnegotiable.Requirements must be met for the specificationsto be satisfied.Specifications describe requirements. In otherwords, specific terms and numerical values withthe measurement units are listed so that it is clear

what issues are considered important.The expectations for performance, quality, orcondition is expressly defined.



Two important elements inSpecifications

The numbers used in writing specs address twoimportant elements in Specifications :

MINIMUMS&

TOLERANCES



MinimumsA minimum is the least or low acceptable valuefor any given parameter or dimension.

Establishing minimums can be very difficult task because it is these values that encompassperformance, appearance, and quality of theproduct.



TolerancesA tolerance describes the range of acceptable values,or in other words, it describes allowable deviationsfrom specified values.Tolerances may be listed in several ways; as range

from X to Y, as plus/minus value such as X + Y, or as aminimum with any value greater than the value listedis being acceptable.A major problem with tolerances is that they canaccumulate or stack up in a product. The result is an

unacceptable product, even though no singlespecification is outside the acceptable limit.Tolerances are included when a range is acceptable.However, not all the specs include tolerances.



Key element in SpecificationThe final key element in specifications is the inclusionof procedures for analysis and evaluation. Theprocedure, test method, or process must be identifiedin detail in the specification.In terms of materials performance, this detailedprocedure usually refers to a standard test method,such as those developed by ASTM or AATCC.In terms of other aspects, such as product dimensions,diagrams and detailed explanations or procedures

may be included. Identification of procedures iscritical, because they ultimately measure whether theproduct conforms to specifications and is acceptableto the company and its target.



Types of SpecificationCompanies developspecifications for a product or a

material asan open orclosed specification.





Open SpecificationAn open specification allows for consideration ofmultiple vendors and includes a description ofcharacter and/or performance desired in the productor material to be purchased.An open specification describes what is wanted andleaves the field open to any supplier who can meetthe requirements specified.Open specifications can include general informationor very specific information regarding fabric mass,resistance to fading, or whatever performance and

design features are required.Open specifications are used to locate appropriatematerials that would satisfy the target market.



Closed specificationA closed specification specifies the exact material,component, or product by the manufacturer orvendor and includes style numbers, trade names,or other specific identifiers. All producers orvendors except for the one specified are restrictedin submitting a bid.

Closed specifications are used for the productionpurposes, pricing and for items that mustincorporate specific materials.



Types of specifications used bythe various industries are listed

in the forthcoming slides. Someof these are having little relationto textile products. Others may be of interest when dealing withspecific textile products



Target Specification

Target specifications relate to the understandingthe company’s focus in terms of the product type,price point, and target market needs andexpectations. Target specifications for textileproducts may be stated in nebulous terms in thecompany’s mission and philosophy statement.

For example, a company describes its missionas “we provide high fashion, upscale furnishingsfor discriminating consumer” incorporates somegeneral aspects related to their market and typesof products produced.



Functional specificationsFunctional specifications for textile productsrelate to performance requirements.Understanding customer expectations forproducts will assist in developing the functionalspecifications.Several laws and regulations incorporatefunctional specifications that must be met. Forexample, functional requirements forflammability are defined by the federal law formattresses and mattress pads.



Product specificationProduct specification includes elements related toproduction: seam and stich type, equipment to beused for each operation, and the aspects relatedto quality.This would include a description of each seam,the thread to be used, seam type, stitch type,stitch density, and the precision of matchingrequired for the plaids and when seams meet. Forexample, what is the acceptable precision whenarms-eye and sleeve seams meet at the underarm



Materials SpecificationMaterials Specification for textile productscombines identification of the characteristics ofeach material (its type, quality characteristics,description, and condition) with the function orperformance aspects.For materials, this would focus on how thematerials, not the product, react to variousconditions of use. Functional specifications needto focus on the product.



Process specificationProcess specification addresses all processes,including pattern and marker making, spreading andcutting, sewing, finishing, packaging and shipment.Product specifications should address the issuesrelated to product quality.For example, specifications for packaging mightaddress the number of items to be placed in a box andthe kind of labels needed on the exterior of the box.These criteria are important for large companies that

operate from distribution centers because of the spaceavailable, conveyor belt size restrictions for movingmerchandise, and in tracking merchandise deliveries.



Inspection specificationsInspection specifications include in-processinspection, final inspection, or acceptableinspection.These specifications, will describe how and whento inspect products



Test specificationsTest specifications may be combined withfunctional and materials specifications.Test specifications describe the procedures tofollow in evaluating the process or the product before, during, or after production.Testing done before production focuses on thematerials – their character and performance.Testing done during the production focuses onthe processes, often during the finishing step.



Acceptance SpecificationsAcceptance Specifications describe the frequency,type and the location of the defects that will beacceptable in the finished product.Acceptance specifications often address aspectsrelate to the appearance, performance, labeling,and packaging.



Installation SpecificationsInstallation Specifications most often relate to theinstallation of the contract and home furnishingsand industrial products.It is the detail instructions necessary for installingproducts on site ready for use.Probably prepared by the design or productdevelopment and engineering divisions.



Use specificationsUse specifications include information andspecial instructions that users will need to enablethem to use the product in its intended manner.Probably prepared by marketing with assistancefrom the design and engineering divisions.



Maintenance specificationsMaintenance specifications gives in details theprocedures to be followed to ensure that theproduct receives correct maintenance at requiredintervals. Probably prepared by the design andmarketing divisions



Disposal Specifications

Identifies any special requirements in terms ofdisposal of the product. May be included with therecyclable products. Probably prepared by thedesign and engineering divisions



Documents

Quality Specification