ارزیابی امکان سنجی بر روی برون سپاری آزمون کیفیت و بازرسی

This paper evaluates the feasibility of outsourcing testing and inspection activities in construction work, based on a survey of interested parties and an evaluation using the Analytic Hierarchy Process (AHP) with experts on quality control. For the AHP, five criteria were adopted and a number of pair-wise comparisons were performed in two stages. Finally, the weighting coefficient to approve the outsourcing was calculated at 0.606, suggesting it more reasonable to permit rather than prohibit outsourcing. Outsourcing of testing/inspection is necessary to enhance the objectivity and expert skill, despite the reduction in the sense of responsibility among the testing technicians and inspectors. However, to initiate outsourcing, it is necessary to first separate the ‘quality testing and inspection’ activities from the ‘quality control’ activities at the job site. Furthermore, the project owner should preferably make the decision to outsource testing and inspection activities and select the testing agency.

Quality control (QC) of construction work is an important process for the construction industry and has been systemized thus far in Korea. However, the recognition of the importance of QC is still low. Thus, there is a tendency for the QC to be performed perfunctorily, with the employment of unqualified persons lacking any direct relation with QC. The appropriation of quality management costs and independence of the quality management organization is still unsatisfactory. In addition, a social Career Development Program for personnel in quality management is insufficient. In general, QC activities include planning for quality management, examining design drawings, checking specifications, purchasing, inspecting and testing. Inspections and tests are fundamental to the quality management process [3] and [7]. As the scales of construction projects have expanded recently, the QC work load including quality testing and inspection at a job site is on the rise. As a result, there is a growing tendency for construction companies to outsource labour-intensive quality testing and inspection activities to external specialized testing agencies [4]. Accordingly, the number of such specialized testing agencies that perform quality testing and inspection at job sites is also on the rise. According to Williams [15] and Schexnayder [13], outsourcing of QC is relatively common place in many countries such as the United States, Japan, Korea and Taiwan. Construction companies gain by being faithful to their inherent QC activities by outsourcing their testing and inspection activities. On the other hand, there exists some concern over the decreased sense of responsibility in case of outsourced quality testing and inspection. Moreover, there is an opinion that outsourcing is not desirable since QC is an inherent part of a contractor’s business [1] and [2]. The purposes of this research are to evaluate the feasibility, effectiveness and necessity of outsourcing tests and inspection works using the Analytic Hierarchy Process (AHP), and to propose policies in connection with the outsourcing of testing/inspection activities.

From the AHP and survey results, it was found that outsourcing tests and inspections is necessary for enhancing the objectivity of quality testing and inspection as well as the expert skills of testing technicians, even though it may be undesirable in that it reduces the sense of responsibility. By means of the AHP, the weighting coefficient to approve of outsourcing testing and inspection was finally calculated at 0.606. Hence, it could be concluded that the outsourcing of tests and inspections at job sites is appropriate. In order to permit outsourcing testing and inspection activities, there is a need to separate the testing technicians and inspectors from the quality management personnel, on the condition that the quality manager at the job site should be attached to the prime contractor. Moreover, it is desirable that the project owner has the authority to decide when to outsource and also to select the testing agency. The scope of the QC activities that can be outsourced should be limited to testing and inspection works, except for small job sites. On the other hand, for qualitative improvement in QC, including the testing and inspection work at a job site, it is necessary to strengthen the specialization and independence of the QC organization. In terms of the administrative aspects, it is necessary to improve the regulations regarding laboratory or testing technicians. With respect to the management of a national technical license, it is necessary to delineate a career in quality management from a career at construction sites.