When admitting steam to a steam piping system, it is imperative to:

The statement about ensuring that no water exists or can accumulate in the piping system when admitting steam is crucial because water can create serious operational issues and safety hazards in a steam system. Steam and water are not compatible under certain conditions. When steam is introduced into a piping system that may contain water, it can lead to a phenomenon known as "water hammer," which occurs when steam rapidly condenses back into water and its pressure increases suddenly, causing shock waves that can damage piping and fittings.

Additionally, having water in the system can lead to inefficiencies in steam transfer and can hinder the proper functioning of the system, including the generation and distribution of heat. To maintain an efficient steam system, it is essential to ensure that it is free of any water to allow the steam to flow freely and perform its intended function without obstruction or risk of damage. Therefore, before admitting steam into the piping system, the presence of water must be thoroughly checked and controlled.