Voltage quality regulation has been an ongoing discussion in many countries in the world to set up a regulatory framework where also voltage dips are included in the national grid codes. Regarding voltage dips, the regulatory framework is useful for establishing the coordination between the network operators, the equipment manufacturers, and the customers. The voltage dip regulation can provide benefits for the involved parties. By defining the responsibilities for the network operators and the customers, it can help distribution system operators to evaluate the quality of supply voltage and to take possible measures when the number of dips exceed the reference values defined in the regulation. The regulatory framework can also help customers to make an economic analysis for choosing appropriate mitigation methods to reduce the expected economic damages caused by voltage dips. This article presents two approaches for classifying different types of voltage dips into various clusters. Using datasets of voltage dips from the Dutch MV networks, the paper also describes the methodology for setting limits on the number of voltage dips for the regulatory purpose.