Construction is almost one of the main and most employed industries in all countries. Occupational health and safety of employees and workers are essential concern of these activities in this field. As the construction activities are diverse and complex, more risks can be observed. Belittling the importance of the safety increased the expense and somehow begets non-atoneable accidents (of the beneficiary). Therefore, it is essential to follow national protective and safety aspects to prevent and dominate the accidents disasters and their consequences. Current research has been carried out to determine the safety factors affecting construction sites and to rank them with help of statistical techniques. In this study for the first step, the attributes which can influence the construction safety based on experts’ ideas and literature review were determined. Afterwards, apropos of the acquired attributes, applying Likert scale, a questionnaire was prepared for evaluation of the relative importance of each variable. The filled questionnaires by construction experts and project managers were analyzed by and applied attributes were ranked by t-test analysis. Thereafter the results examined and some strategies were proposed. Besides the t-test, factor analysis was undertaken for constructing smaller set of variables. At last, the two representatives of construction worksites in petrochemical and urban projects were analyzed based on the Florence Ling checklist ( Singapore ), which had been prepared for assessing the safety condition of construction worksites. Finally the results were oriented to Iran condition with the aid of domestic expert points of view.