İnşaat işletmelerinde kalite yönetimi
İnşaat işletmelerinde kalite yönetimi
Dosyalar
Tarih
1996
Yazarlar
Akkum, İlhami
Süreli Yayın başlığı
Süreli Yayın ISSN
Cilt Başlığı
Yayınevi
Fen Bilimleri Enstitüsü
Özet
Kalite sözcüğü kullanım amacına göre değişik anlamlar ifade edebilir. Tek bir cümle ile açıklamak gerekirse, kalite istenen özelliklere uygunluktur Kalite kontrol ve kalite yönetimi kavramları arasındaki en önemli fark birincisinin ürün üzerinde, ikincisinin üretim sistemi üzerinde odaklanma sı dır. Sektörel analizler inşaattaki üretim hatalarının yalnızca küçük bir bölümünün teknik sebeplerden kaynaklandığını göstermektedir. Hataların çoğunluğu yönetim yapılarının uygunsuzluğundan, eğitim eksikliğinden, ve işin en düşük teklife ihale edilmesi sonucu oluşan ticari baskılardan kaynaklanmaktadır. inşaat sektörünün özelliği, işverenin ihtiyaçlarının tasarımcılar tarafından çizimler ve şartnameler halinde tanımlanmış ve taahhüt mukavelesinde yer almış olmasıdır. Bu durumda müteahhit açısından kalite "çizimlere ve şartnamelere uygunluktur"tur. Kalite sisteminin amacı firmanın ürettiği mal veya hizmetin müşterinin kalite beklentilerine uygun olmasının sağlanmasıdır. Kalite sistemi, kalite güvencesini ve kalite kontrolü içerir. Uluslararası kabul görmüş sözleşme düzenlemeleri, söz konusu projelerin gerçekleştirilmesinde uygulanması gereken kalite sistemlerinin çerçevesini oluşturur. Kurulan sistemin işlevselliği ve etkinliği ancak amaca uygun, periyodik denetim ve değerlendirmelerle sağlanabilir. Ne kadar özenle ve kapsamlı hazırlanmış olursa olsun, hiç bir kalite sistemi insanlar olmadan devreye sokulamaz. İnşaat sektörünün en önemli sorunlarından birisi bu sektörde çalışanların eğitim eksikliğidir, inşaat işlerinin mevsimsel veya dönemsel olarak azalıp çoğalması, şantiyelerin coğrafi konumunun sürekli değişmesi, şirketlerin mevcut projelerin bitiminden sonra alacakları işleri tahmin edememesi insana yapılacak yatırımı engellemektedir. Kalite elkitapları ve ilgili dokümantasyonun amaçlarından biri de şirketin kalite sistemi hakkında inşaat projelerini ihaleye çıkartan işveren idarelere bilgi vermektir. Projenin gerçekleştirilmesine yönelik iş planları (örneğin inşaat planı, maliyet planı, vs.) yapılırken, şartnamelerde belirtilen standartların nasıl sağlanacağına yönelik kalite planlan da hazırlanmalı ve bu planlar günlük şantiye yönetim faaliyetlerinin bir parçası olmalıdır. Kalite sistem standartlarına uyma zorunluluğu bir çok gelişmiş ülke tip mukavelesinde yerini almakta olup, dışa açılma, yabancı yatırımcıların Türkiye'ye gelişi, özelleştirme sonucu yapılacak iyileştirme ve genişletme çabalan gibi nedenlerle ülkemizde yapılacak ihalelerin dosyalarında yakında karşılaşmak için hazırlıklı olunmalıdır. Kalite sistemi yalnızca en tepeden başlarsa kalıcı olabilir. Yönetim Kurulu Başkanı ve üyeleri şirketin kalite felsefesinin temellerini atmalı, değişimin sürdürülmesi için doğru kişilerin görevlendirilmesini sağlamalıdır.
The quality is the totaiity of features and characteristics of a product ör service that bear on its ability to satisfy stated ör implied needs. The quality assurance is defıned as ali planned and systematic actions necessary to provide adequate confidence that a product ör service will satisfy given requirements for quality. The most majör difference between quality control and quality assurance is that the former may identify the non-compliance only after the product is manufactured whereas quality assurance aims to guarantee the quality by controlling the system. Sectoral analyses reveal a minör portion of the construction defects are due to technical causes. Most of them originate from inappropriate management structures, lack of education and commercial pressures emanating from the acceptance of the lovvest bid. Lack of quality in the constructed facilities constitute the most majör concern in construction managers career; in such a case efforts for controlling cost and time may turn to be useless. Clients require facilities they procure possess considerably long service lives and hold contractors legally liable for years because of their quality. The increasing intemational competition, the European market being unified, new legal measures for environmental protection bring about new requirements for the quality of the goods and services. in order to form a common basis for such requests the intemational Organization for Standardization have first published in 1987 the İSO 9000 series Ouality Management and Ouality Assurance Standards vvhich have been adopted by many countries, as well as the European Standards Committee under the EN 29000 title. Although worded using the technology of an industrial company the İSO 9000 can be applied for the services sectors such as finance, insurance, tourism, health, ete. in the construction industry clients needs are translated by the designers in the form of drawings and specifications vvhich are integral parts of the construction contracts. Therefore from the point of the contractors the quality can be described as conformance to drawings and specifications. The aim of a quality system is to ensure that the company's product ör service meets the customer's quality requirements. The quality system incorporates both quality assurance and quality control. The intemationally accepted forms of contract constitute the framework of the quality systems that shall be implied for the execution of the projects in question. Very few organizations are vvithout systems of any kind. in smal! businesses where the person in charge can observe the activities of ali employees and can personally check that no defective goods ieave the premises, the system can be very simple indeed. Hovvever as organization become larger and more complex, there comes a point at which it is impossible for öne person to undertake personal supervision of ali that goes on and authority has to be delegated. At this point the sensible manager will pubiish the rules which have to be observed and the procedures which are to be followed by members of staff exercising authority on his behalf. Some of these rules and procedures will relate to administrative and commercial matters, others will define how customer satisfaction with the products and services of the organization is to be assured. The latter category will form the kemel of the quality system. Most majör contracting companies operate as groupings of subsidiary companies ör divisions, each of which concentrates on a particular market sector and has its own directors who will have autonomy within their company, subject to general policies and financial targets set by the board of directors and chief executive of the group. Typically, the chief executives of the subsidiary companies will also be directors of the main board of the group so that they can ansvver for their companies1 performance and have a voice in the overall determination of policy. The success of the quality system will depend heavily on the personal qualities of the Ouality Manager, it is a task vvhich requires tact, integrity, persuasiveness and patience as well as a broad technical understanding. Impartiality and credibility demand a position vvhich is free from immediate commercial pressures, and the need to command respect requires a status vvhich will indicate that the holder has the confidence and support of the chief executive. in the case of a majör contracting group, the role could be combined with other technical functions and represented at board level by a group technical director. The activities of subsidiaries operating within a construction group may include buildings, infrastructure, transportation, energy, steel structures, ready-mixed concrete, forestry products, building materials and general contracting. To maintain a common thread the first step is to issue an instruction requiring each company to appoint a director ör senior manager to take responsibility for the establishment of a company quality system in accordance with group policy. The person appointed should be directly responsible to the chief executive of the operating company and have the necessary delegated authority and freedom from production pressures to enable him to discharge his duties effectively. This person vvould also be the principal point of contract with the group quality assurance manager. The contracts undertaken by construction companies may vary in size from those supervised by just öne ör two full-time staff, to mega projects requiring ü hundreds of technical and administrative persons. The larger projects necessitate a resident quality assurance management team implementing a project quality system whereas smaller projects can be adequately supported on a visiting basis either by the company quality assurance manager ör by the regional representative. The functionality and efficiency of the established system can only be assured through periodic auditing and reviews vvhich should be set forth by specific procedures. The primary objective of such activities are to diagnose any non-compliance and to facilitate the implementation of the system. The İSO 9000 standard acknowledges that change is a constant and that quality systems are never perfect. Management must pay consistent attention to the quality system to make sure that it improves and adjusts to change. The essential characteristics of a quality audit is that it is undertaken by independent persons ör bodies having no direct interest ör responsibility in respect of the organization ör project being examined. Audits may be intemal, ör they may be undertaken by second parties (clients) ör they may be carried out by third parties acting on behalf of a client. No matter how carefully and comprehensive a quality system may be, it can only be put into effect by people, If the people do not know how to operate it, ör if they do not want to operate it, then failure wîll result. The İSO 9000 standard recognize how vital personnel are to the success of a quality system. Accordingly, the standard sets forth detailed requirements and guidelines goveming qualification, training, and motivation of employees whose work affects quality in any way. The construction industry suffers from the lack of training. The cyclic nature of the construction work load and the geographical changes in the location of the sites make it difficult to look beyond the end of the current contract and prevent long term investment in people. Documentation is central to İSO 9000 and there are many references to documentation vvithin the standard. İSO 9000 requires only a reasonable and prudent level of documentation and even cautions companies against overdoing it. Ouality system documentation is usually composed of several different levels. The standard describes each of these levels without mandating any of them. This is, önce again, an area where the standard allovvs flexibility for the application and implementation. The most important document of the quality system is the quality manual. The standard suggests that methods be established for making changes to the manual and controlling its distribution. But novvhere does the standard prescribe the exact contents. iii The second and more detailed group of quality system documentation relates to plans and procedures. there is nothing in the standard that requires the development of these documents. Hovvever, the standard calls for development of documents of which the absence would adversely affect quaiity. Procedures are specific how-to's for carrying out activities outlined in öne ör more quality plans. They should include cross-references to the related quality plan and, where appropriate, to the quality manual. Operating procedures are not necessarily job descriptions (though they can be developed as such); they are specific to the process, not to an individual. The classification, quantity, scope and length of the procedures vary depending on the structure of every company. it is unfortunate fact that many excellent managers refrain from producing written instructions for work for which they are responsible. They know what has to be done and can teli people what to do, but they lack the ability to organize their thoughts on paper. There is a further benefit of producing documented instructions. Very often the assembly of facts, the thought and the analysis necessary to prepare a vvritten instructions can expose areas of vveakness ör duplication of inefficient practices which are followed unquestioningly because they are part of a tradition. Most construction work is carried out on a project basis. Thus contractors can expect at any öne time to be working on behalf of a number of clients and on a variety of different classes of work. Circumstances inevitably arise when the contractor's standard procedures are clearly unsuitable ör inadequate for application on a particular project. To make the task of preparing procedures and instructions less impleasant to the busy managers and to achieve a uniformity in their format procedures for the preparation and administration of instructions and procedures should be set forth. The İSO 9000 standard does not say that every activity on the site has to be covered by a written work instruction. it is obvious that the absence of drawings, ör specifications ör welding instructions would have an adverse affect on quality. But it does not require a v/ritten instruction for the removal of rubbish. it is a rare event for a design document to remain unchanged throughout its lifetime. Moreoften it will be issued in a succession of modified editions. There is a variety of reasons why this should be so: circumstances may have changed, equipment may have become obsolete, a better method may have been found, ör the purchasing department may not agree with the supplier. VVhatever the reason, only the correct editions of documents should be used for any task. iv Organizations in receipt of documents, such as construction sites, should establish similar procedures for controlling the receipt and re-issue of documents. On a small site, a conventional drawing register is usually ail that is needed. Large sites, particularly those empioying substantial numbers of subcontractors should introduce computerized systems. The purpose of compiling records is to chronicle what has taken place and provide reliable, factual information for future use. in a quality system, records are required in order to demonstrate that the system is functioning satisfactorily and that the required standards are being achieved. They supply objective evidence to enable a contractor to demonstrate that his operations are controlled and the construction will comply with the requirements. Öne of the purposes of a quality manual and related documentation is to provide information on an organization's quality system for the benefıt of potential employers. Manuals may be included in sales packages, ör submitted for prequalifıcation ör included in a tender. The quaiity plans should be made part of everyday site management like the design plans, construction plans, cost plans, ete. Verification of compliance with specifications commences vvhen materials ör supplies are received at the site. The criteria for compliance are usually defined in the specifications, together with the appropriate sampling and testing regimes. The extent to which materials should be inspected on receipt should be carefully planned, bearing in mind the costs of inspection and the possible penalties vvhich may arise from building sub-standard items into the works. Procedures should ensure that non-conforming materials are isolated and prevented from being used. During the course of the work the checks and test scheduled in the inspection and Test Plans are carried out in order to control quality. Under conventional arrangements, the primary responsibility for quality control rests vvith the contractor ör supplier, with the Employer ör his representative undertaking a monitoring role. The purpose of quality assurance system standards is to safeguard the independence of inspectors and to protect them from commercial pressures. The question arises, hovveven Do quality control staff as conventionally deployed on construction work have sufficient organizational freedom and authority to discharge their responsibilities without pressure? Should there not be at each site, an inspection team vvhich is separate from the engineers in charge of getting work done and vvhich reports to a higher level of management? The ansvver to this question should depend on the contractual arrangements betvveen the employer and the contractor and the degree of supervision exercised by the employer ör his representatives. v The final phase of a site quality management system is the provision of objective evidence that work has been carried out in compliance with the drawings and specifications. ISO 9000 require that records should be maintained both to provide proof of compliance and to demonstrate the effectiveness of the quality system. Virtually every type of business acquires some form of product or service from outside suppliers. Input ranges from basic raw materials (such as concrete aggregates) to finished goods of incredible complexity (such as a fire alarm system). In the era of decentralization and spin-offs, vertical integration is out-of-fashion and businesses depend upon outside suppliers and subcontractors. The ISO 9000 quality system standard recognizes the vital impact that suppliers and subcontractors have on a company's quality system. Its requirements for subcontractor relationships are based upon a philosophy of open and close communication between company and sub-contractor. These guidelines are meant to create clear understanding of requirements on both side. An ISO 9000 procurement system shall create continual improvement between supplier and subcontractor and avoid or quickly settle quality disputes. Definition of the requirement normally commences with the preparation of the requisition which provides a description of the materials, equipment or services required and forms an instruction to the buying staff. The preparation of requisitions should be a technical function and for the major projects should be delegated to suitably qualified personnel within the project team. Quality assurance reviews are sometimes also made part of inquiry requisitions, particularly if there is a likelihood that the quality assurance requirements might have a significant effect on the tenderer's quotations including potential delays. It is increasingly common to have the quality system standards having their places in the contractual arrangements of developed countries; foreign investments, upgrading and expansion of privatized facilities are likely to foster the inclusion of such requirements in the construction tender documents issued for works in Türkiye. Any construction organization contemplating the establishment of a quality system whether to achieve certification by an accredited body, to prequalify for a tender, or to improve its own efficiency, should face a long and difficult path. Due to the properties of the construction industry discriminating it from others the management of construction sites is a difficult task and it is very important that the managers should have access to the latest and most effective management techniques including the quality assurance systems. VI Management gets the employees which it deserves. If there is corruption at the top of an organization sooner or later there will be corruption at lower levels as well. This will inevitably lead to poor quality and customer dissatisfaction. Conversely, staff respect honesty in their managers and will tend to apply similar standards in the conduct of their own affairs. To set the standard the chief executive must make a public statement of his personal attitude in these matters. The establishment of a quality system depend on the commitment of the top management. The chief executive and his directors must cast the foundations of company's quality philosophy and must appoint the appropriate persons to sustain the development. The established and documented quality system shall not mean a decrease in quality system manager's workload; the circumstances vary continually and the future is impredictable as ever. Since nothing endures but change the quality system must be able to adjust without attempting to preserve the status-quo. Construction companies might face costs of poor quality at the projects they had completed due to repairs carried out, after sales remedial works, legal representation, court costs, compensation payments etc. Companies which have attempted to quantify these costs arrive at totals varying between 10% and 40% of turnover. However, the costs of quality systems do not exceed 1% at conventional projects, perhaps reaching a maximum of 5% at nuclear and off-shore works.
The quality is the totaiity of features and characteristics of a product ör service that bear on its ability to satisfy stated ör implied needs. The quality assurance is defıned as ali planned and systematic actions necessary to provide adequate confidence that a product ör service will satisfy given requirements for quality. The most majör difference between quality control and quality assurance is that the former may identify the non-compliance only after the product is manufactured whereas quality assurance aims to guarantee the quality by controlling the system. Sectoral analyses reveal a minör portion of the construction defects are due to technical causes. Most of them originate from inappropriate management structures, lack of education and commercial pressures emanating from the acceptance of the lovvest bid. Lack of quality in the constructed facilities constitute the most majör concern in construction managers career; in such a case efforts for controlling cost and time may turn to be useless. Clients require facilities they procure possess considerably long service lives and hold contractors legally liable for years because of their quality. The increasing intemational competition, the European market being unified, new legal measures for environmental protection bring about new requirements for the quality of the goods and services. in order to form a common basis for such requests the intemational Organization for Standardization have first published in 1987 the İSO 9000 series Ouality Management and Ouality Assurance Standards vvhich have been adopted by many countries, as well as the European Standards Committee under the EN 29000 title. Although worded using the technology of an industrial company the İSO 9000 can be applied for the services sectors such as finance, insurance, tourism, health, ete. in the construction industry clients needs are translated by the designers in the form of drawings and specifications vvhich are integral parts of the construction contracts. Therefore from the point of the contractors the quality can be described as conformance to drawings and specifications. The aim of a quality system is to ensure that the company's product ör service meets the customer's quality requirements. The quality system incorporates both quality assurance and quality control. The intemationally accepted forms of contract constitute the framework of the quality systems that shall be implied for the execution of the projects in question. Very few organizations are vvithout systems of any kind. in smal! businesses where the person in charge can observe the activities of ali employees and can personally check that no defective goods ieave the premises, the system can be very simple indeed. Hovvever as organization become larger and more complex, there comes a point at which it is impossible for öne person to undertake personal supervision of ali that goes on and authority has to be delegated. At this point the sensible manager will pubiish the rules which have to be observed and the procedures which are to be followed by members of staff exercising authority on his behalf. Some of these rules and procedures will relate to administrative and commercial matters, others will define how customer satisfaction with the products and services of the organization is to be assured. The latter category will form the kemel of the quality system. Most majör contracting companies operate as groupings of subsidiary companies ör divisions, each of which concentrates on a particular market sector and has its own directors who will have autonomy within their company, subject to general policies and financial targets set by the board of directors and chief executive of the group. Typically, the chief executives of the subsidiary companies will also be directors of the main board of the group so that they can ansvver for their companies1 performance and have a voice in the overall determination of policy. The success of the quality system will depend heavily on the personal qualities of the Ouality Manager, it is a task vvhich requires tact, integrity, persuasiveness and patience as well as a broad technical understanding. Impartiality and credibility demand a position vvhich is free from immediate commercial pressures, and the need to command respect requires a status vvhich will indicate that the holder has the confidence and support of the chief executive. in the case of a majör contracting group, the role could be combined with other technical functions and represented at board level by a group technical director. The activities of subsidiaries operating within a construction group may include buildings, infrastructure, transportation, energy, steel structures, ready-mixed concrete, forestry products, building materials and general contracting. To maintain a common thread the first step is to issue an instruction requiring each company to appoint a director ör senior manager to take responsibility for the establishment of a company quality system in accordance with group policy. The person appointed should be directly responsible to the chief executive of the operating company and have the necessary delegated authority and freedom from production pressures to enable him to discharge his duties effectively. This person vvould also be the principal point of contract with the group quality assurance manager. The contracts undertaken by construction companies may vary in size from those supervised by just öne ör two full-time staff, to mega projects requiring ü hundreds of technical and administrative persons. The larger projects necessitate a resident quality assurance management team implementing a project quality system whereas smaller projects can be adequately supported on a visiting basis either by the company quality assurance manager ör by the regional representative. The functionality and efficiency of the established system can only be assured through periodic auditing and reviews vvhich should be set forth by specific procedures. The primary objective of such activities are to diagnose any non-compliance and to facilitate the implementation of the system. The İSO 9000 standard acknowledges that change is a constant and that quality systems are never perfect. Management must pay consistent attention to the quality system to make sure that it improves and adjusts to change. The essential characteristics of a quality audit is that it is undertaken by independent persons ör bodies having no direct interest ör responsibility in respect of the organization ör project being examined. Audits may be intemal, ör they may be undertaken by second parties (clients) ör they may be carried out by third parties acting on behalf of a client. No matter how carefully and comprehensive a quality system may be, it can only be put into effect by people, If the people do not know how to operate it, ör if they do not want to operate it, then failure wîll result. The İSO 9000 standard recognize how vital personnel are to the success of a quality system. Accordingly, the standard sets forth detailed requirements and guidelines goveming qualification, training, and motivation of employees whose work affects quality in any way. The construction industry suffers from the lack of training. The cyclic nature of the construction work load and the geographical changes in the location of the sites make it difficult to look beyond the end of the current contract and prevent long term investment in people. Documentation is central to İSO 9000 and there are many references to documentation vvithin the standard. İSO 9000 requires only a reasonable and prudent level of documentation and even cautions companies against overdoing it. Ouality system documentation is usually composed of several different levels. The standard describes each of these levels without mandating any of them. This is, önce again, an area where the standard allovvs flexibility for the application and implementation. The most important document of the quality system is the quality manual. The standard suggests that methods be established for making changes to the manual and controlling its distribution. But novvhere does the standard prescribe the exact contents. iii The second and more detailed group of quality system documentation relates to plans and procedures. there is nothing in the standard that requires the development of these documents. Hovvever, the standard calls for development of documents of which the absence would adversely affect quaiity. Procedures are specific how-to's for carrying out activities outlined in öne ör more quality plans. They should include cross-references to the related quality plan and, where appropriate, to the quality manual. Operating procedures are not necessarily job descriptions (though they can be developed as such); they are specific to the process, not to an individual. The classification, quantity, scope and length of the procedures vary depending on the structure of every company. it is unfortunate fact that many excellent managers refrain from producing written instructions for work for which they are responsible. They know what has to be done and can teli people what to do, but they lack the ability to organize their thoughts on paper. There is a further benefit of producing documented instructions. Very often the assembly of facts, the thought and the analysis necessary to prepare a vvritten instructions can expose areas of vveakness ör duplication of inefficient practices which are followed unquestioningly because they are part of a tradition. Most construction work is carried out on a project basis. Thus contractors can expect at any öne time to be working on behalf of a number of clients and on a variety of different classes of work. Circumstances inevitably arise when the contractor's standard procedures are clearly unsuitable ör inadequate for application on a particular project. To make the task of preparing procedures and instructions less impleasant to the busy managers and to achieve a uniformity in their format procedures for the preparation and administration of instructions and procedures should be set forth. The İSO 9000 standard does not say that every activity on the site has to be covered by a written work instruction. it is obvious that the absence of drawings, ör specifications ör welding instructions would have an adverse affect on quality. But it does not require a v/ritten instruction for the removal of rubbish. it is a rare event for a design document to remain unchanged throughout its lifetime. Moreoften it will be issued in a succession of modified editions. There is a variety of reasons why this should be so: circumstances may have changed, equipment may have become obsolete, a better method may have been found, ör the purchasing department may not agree with the supplier. VVhatever the reason, only the correct editions of documents should be used for any task. iv Organizations in receipt of documents, such as construction sites, should establish similar procedures for controlling the receipt and re-issue of documents. On a small site, a conventional drawing register is usually ail that is needed. Large sites, particularly those empioying substantial numbers of subcontractors should introduce computerized systems. The purpose of compiling records is to chronicle what has taken place and provide reliable, factual information for future use. in a quality system, records are required in order to demonstrate that the system is functioning satisfactorily and that the required standards are being achieved. They supply objective evidence to enable a contractor to demonstrate that his operations are controlled and the construction will comply with the requirements. Öne of the purposes of a quality manual and related documentation is to provide information on an organization's quality system for the benefıt of potential employers. Manuals may be included in sales packages, ör submitted for prequalifıcation ör included in a tender. The quaiity plans should be made part of everyday site management like the design plans, construction plans, cost plans, ete. Verification of compliance with specifications commences vvhen materials ör supplies are received at the site. The criteria for compliance are usually defined in the specifications, together with the appropriate sampling and testing regimes. The extent to which materials should be inspected on receipt should be carefully planned, bearing in mind the costs of inspection and the possible penalties vvhich may arise from building sub-standard items into the works. Procedures should ensure that non-conforming materials are isolated and prevented from being used. During the course of the work the checks and test scheduled in the inspection and Test Plans are carried out in order to control quality. Under conventional arrangements, the primary responsibility for quality control rests vvith the contractor ör supplier, with the Employer ör his representative undertaking a monitoring role. The purpose of quality assurance system standards is to safeguard the independence of inspectors and to protect them from commercial pressures. The question arises, hovveven Do quality control staff as conventionally deployed on construction work have sufficient organizational freedom and authority to discharge their responsibilities without pressure? Should there not be at each site, an inspection team vvhich is separate from the engineers in charge of getting work done and vvhich reports to a higher level of management? The ansvver to this question should depend on the contractual arrangements betvveen the employer and the contractor and the degree of supervision exercised by the employer ör his representatives. v The final phase of a site quality management system is the provision of objective evidence that work has been carried out in compliance with the drawings and specifications. ISO 9000 require that records should be maintained both to provide proof of compliance and to demonstrate the effectiveness of the quality system. Virtually every type of business acquires some form of product or service from outside suppliers. Input ranges from basic raw materials (such as concrete aggregates) to finished goods of incredible complexity (such as a fire alarm system). In the era of decentralization and spin-offs, vertical integration is out-of-fashion and businesses depend upon outside suppliers and subcontractors. The ISO 9000 quality system standard recognizes the vital impact that suppliers and subcontractors have on a company's quality system. Its requirements for subcontractor relationships are based upon a philosophy of open and close communication between company and sub-contractor. These guidelines are meant to create clear understanding of requirements on both side. An ISO 9000 procurement system shall create continual improvement between supplier and subcontractor and avoid or quickly settle quality disputes. Definition of the requirement normally commences with the preparation of the requisition which provides a description of the materials, equipment or services required and forms an instruction to the buying staff. The preparation of requisitions should be a technical function and for the major projects should be delegated to suitably qualified personnel within the project team. Quality assurance reviews are sometimes also made part of inquiry requisitions, particularly if there is a likelihood that the quality assurance requirements might have a significant effect on the tenderer's quotations including potential delays. It is increasingly common to have the quality system standards having their places in the contractual arrangements of developed countries; foreign investments, upgrading and expansion of privatized facilities are likely to foster the inclusion of such requirements in the construction tender documents issued for works in Türkiye. Any construction organization contemplating the establishment of a quality system whether to achieve certification by an accredited body, to prequalify for a tender, or to improve its own efficiency, should face a long and difficult path. Due to the properties of the construction industry discriminating it from others the management of construction sites is a difficult task and it is very important that the managers should have access to the latest and most effective management techniques including the quality assurance systems. VI Management gets the employees which it deserves. If there is corruption at the top of an organization sooner or later there will be corruption at lower levels as well. This will inevitably lead to poor quality and customer dissatisfaction. Conversely, staff respect honesty in their managers and will tend to apply similar standards in the conduct of their own affairs. To set the standard the chief executive must make a public statement of his personal attitude in these matters. The establishment of a quality system depend on the commitment of the top management. The chief executive and his directors must cast the foundations of company's quality philosophy and must appoint the appropriate persons to sustain the development. The established and documented quality system shall not mean a decrease in quality system manager's workload; the circumstances vary continually and the future is impredictable as ever. Since nothing endures but change the quality system must be able to adjust without attempting to preserve the status-quo. Construction companies might face costs of poor quality at the projects they had completed due to repairs carried out, after sales remedial works, legal representation, court costs, compensation payments etc. Companies which have attempted to quantify these costs arrive at totals varying between 10% and 40% of turnover. However, the costs of quality systems do not exceed 1% at conventional projects, perhaps reaching a maximum of 5% at nuclear and off-shore works.
Açıklama
Tez (Yüksek Lisans) -- İstanbul Teknik Üniversitesi, Fen Bilimleri Enstitüsü, 1996
Anahtar kelimeler
Kalite yönetimi,
İnşaat işletmeleri,
Quality management,
Construction enterprises