Electrical contractors typically allocate 33 to 50 percent of a project’s total contract budget to labor costs. Labor is the project element containing the most risk; as a result, financial success hinges upon the ability to manage labor effectively and maintain worker efficiency. In circumstances of schedule acceleration and other malevolent project conditions various situations can arise decreasing the labor’s efficiency or productivity. These situations, commonly referred to as factors affecting labor productivity, can be initiated either by the general/CM contractor or by the project owner. This report seeks to quantify these factors. Productivity factors that are quantified include shift work, overmanning, owner-furnished items, beneficial occupancy, stacking of trades, and cumulative impacts.