My article earlier this year about line breaks on relief valve vent lines that are attached to a header/manifold got a lot of you to ask more questions about the practice of “line breaking” (or as some call it “process opening”). I have tried to answer each question but thought it may be helpful to explain the fundamentals of safe line breaking. As we know, “line breaking” is the one safe work practice that OSHA and EPA mention in their process safety standards yet provides ZERO guidance on. We can not even find an RAGAGEP or consensus standard for guidance; however, we do have some excellent historically practices we can rely on.