What is recommended to prevent contamination when sealing pipes?

When sealing pipes, it is recommended to never add sealant to the first two threads to prevent contamination. This principle is important because sealant can enter the flowing medium within the pipe and create contamination, particularly with substances that are sensitive to foreign materials, such as drinking water or food-grade liquids. By leaving the first two threads free of sealant, it helps to maintain a clean connection and prevents any sealant from interfering with the flow of materials or compromising the integrity of the system.

This approach also ensures that the seal remains effective without introducing extraneous materials that could cause clogs or degradation over time. Maintaining a clean sealing environment is especially crucial in applications where purity and safety are prioritized.