Exploratory study of the major factors influencing craft productivity in nuclear power plant construction. Volume I

The data for this study were collected at six nuclear power plant construction sites spread throughout the United States. The geographical distribution included two projects from the Midwest and one site from each the Deep South, North Central, Southwest, and Northeast regions of the nation. The range for stage of completion varied from between approximately four and seventy-seven percent. Two of the projects were utilizing boiling water reactors (BWR) while the balance of the sites made use of the pressurized water reactor (PWR) systems. All of the installations had generating capacities approximately equal to 1200 megawatts per unit. The primary objective of the study was to provide a comprehensive investigation of the most influential factors adversely affecting craft productivity by means of a sampling comprised of five hundred seventy-six union and open shop carpenters, electricians, and pipefitters. The overall average amount of time lost due to delays obtaining materials and tools, overcrowded working conditions, interferences between crews, postponements relating to quality control inspections, and waiting for and/or receiving instructions was estimated by the tradesmen to be 24.12 manhours per individual on a weekly basis. Thus, a minimum of 60.3% of each tradesman's time is lost due to one of the aforementioned predicaments. Conversely, this figure accounts for a maximum possible level of direct work activity equal to 39.7% and is not inclusive of any personal breaks or late starts/early quits. The combined mean duration that was speculated for rework activities at all six sites totaled 5.77 manhours per craftsman per week. The summation of these two estimates yields a value of 29.89 manhours showing that only slightly more than twenty-five percent of each worker's time is allocated to productive endeavors for activities being engaged in for the first time