This article is dedicated to identifying, screening and calculating quality costs items based on the traditional 'Prevention-Appraisal-Failure' (PAF) model in all four categories of prevention cost, appraisal cost, internal failure cost and external failure cost; for this purpose, the quality cost items are listed according to the BS 6143 standard, Juran's quality handbook and opinions of the experts; this list are refined using the Lawshe technique. In order to calculate the quality cost items in the four groups, formulas based on expert opinions have been developed and the quality cost items have been calculated and analyzed for two consecutive years.