Distillation columns allow separation of fluid mixtures based on their boiling points. As vapors rise through the column, different components will condense at different temperatures and accumulate for withdrawal. Distillation columns will have a wide range of temperatures throughout. Fluids, especially at the lower end can be dirty and cause coating and plugging of equipment. Overfill is a risk especially during plant start-up and before equilibrium is reached between the liquid and gas flow. If an overfill occurs, process media typically ends up in the flare system for hydrocarbons with the risk of a dangerous incident / explosion. Some users may prefer to measure the level directly in the tower while others may prefer the serviceability of cages with valves. If direct measurements are required, DP level is an appropriate solution. If bypass chamber is used, Guided Wave Radar together with a High-level alarm with point level measurement is the recommended solution.