Time standards belong to the key indicators of production process effectiveness. The paper discusses time standard setting in the production process. One of the important stages of the production process is assembly, which is a crucial stage in case of manufacturing customized products. The aim of the article is to show the methods of time standard setting which facilitate assembly planning. Specific goals of the article are focused on finding common attributes useful in assembly tasks characteristics and changeover, as well as finding value intervals helpful in assembly description. Shortening the product lifecycle, new product development and product customization bring about the development of a modular reconfigurable assembly line. The development of flexible assembly lines requires standards related to typical assembly tasks and tools. Reconfiguration and balancing assembly lines require a knowledge base related to time standards. This article presents examples of typical tasks, tools and time standards for planning product assembly and changeover which use the assembly and disassembly processes.