A subcontractor selection and evaluation method in terms of occupational health and safety and a field study

If we divide the process of a project into three stages, which are design, construction and consignment, choosing subcontractors will be the first stage of construction. This study is conducted in order to help employers to evaluate subcontractors according to Occupational Health and Safety. Although employers can guarantee factors such as cost, quality and time with contracts and assurances, they cannot guarantee Occupational Health and Safety. Due to this reason, employers should be very cautious while deciding on subcontractors. Compared to Occupational Health and Safety, it is much easier to make comparisons with tangible data on things like cost, experience, and financial power. This study is aimed to help employers to evaluate certain criteria in order to accumulate results that will aid them to assess Occupational Health and Safety of subcontractors. This study consists of four chapters: • Occupational Health and Safety • Construction Industry and Choosing Subcontractors • Determining Criteria on How to Choose Subcontractors and the Weight of these Criteria Regarding to Occupational Health and Safety • Field Studies Law No. 6331 on Occupational Health and Safety, Law No. 4587 on Labor Law, cause and effect of occupational accidents, measures that must be taken, and Occupational Health and Safety Management Systems are explained in detail in the chapters about Occupational Health and Safety. In these chapters, management systems OHSAS 18001, ILO – OSH 2001 and CMAA, which are all Occupational Health and Safety Management Systems acknowledged worlwide, are also elaborated on. In the chapter on Construction Industry and Choosing Subcontractors these topics are presented: Statistics, the importance and situation of construction in Turkey, Public Procurement Law, Turkish Code of Obligations (Act No. 6098), and things that should be taken into account while choosing subcontractors. After detailed research, six most important criteria while choosing a subcontractor are determined as cost, time, quality, experience, occupational safety, and financial power of a subcontractor. After pointing out the fact that one of the most important criteria while choosing a subcontractor is Occupational Health and Safety, another research has been made in order to designate the criteria on Occupational Health and Safety while choosing a subcontractor. There are 26 most common criteria that are found in Turkish and foreign works. Analytic Hierarchy Process is selected in order to assess the weight of these criteria based on the suggested method of this research. Six criteria are excluded from this hierarchy so that this study has a wider field of application. Paired comparison surveys that are written based on this hierarchy were sent out to occupational safety specialists and five surveys, whose consistency levels were acceptable, are included in this study. Weight of the criteria were determined with the help of Superdecision program and a specific weight was calculated for each of these 20 criteria. In order to form a success scale, a chart was sent out to the participants of the survey and they were asked to grade (based on a 0-100 grading system) ratings that were "Successful", "Sufficient", "Average", "Below Average", and "Unsuccessful". A success scale is established by calculating the arithmetic mean of the answers. In the chapter on field studies, this study was practiced on construction projects, and furthermore, Occupational Health and Safety in Turkey was evaluated based on construction projects in different cities. Three different occupational safety specialists that are working in large-scale shopping mall constructions in Adana, Balıkesir and Kırklareli were asked to grade 5 subcontractors based on 20 criteria of AHP method. Weighted average was calculated with survey results and criteria weights. Subcontractors were graded accordingly and evaluated based on the success scale. The results are not ratings that are desirable according to Occupational Health and Safety. Occupational Health and Safety is a very important topic that should be taken into account from the early stages of designing a project. When choosing a subcontractor, if they are evaluated based on this perspective, this will create awareness during the whole processes of a project.