Almost every PSM coordinator builds one eventually. A spreadsheet with the OSHA requirement in the left column, the EPA version next to it, and the IIAR standard that covers the same ground in the third. Green fill wherever the rows line up. It feels like progress, and for about a week it is. Then somebody asks whether the crosswalk means you’re covered, and the honest answer is no. I like crosswalks. They’re the fastest way to see which rulebooks are pointed at your ammonia

Process Safety Information (PSI) is the technical foundation of a Process Safety Management (PSM) program. Your PHAs, operating procedures, mechanical integrity program, and many other PSM activities depend on this information being accurate. Under OSHA 29 CFR 1910.119(d), PSI is divided into three main categories. But what actually belongs in each one? 1. Hazards of the Chemical For an ammonia refrigeration system, this section documents the hazards and properties of anhydro

Direction of flow is one of the factors that go into a valve’s design. Valves have a direction-of-flow arrow either as part of the valve’s forging or markings. We use these arrows to ensure the valve is installed properly. But does that mean that the valve will only operate properly if installed with the arrow matching the flow of the pipe contents? Can valves be installed backwards? Valves will work when installed in either direction. They are normally installed with th

Every pressurized ammonia vessel is designed to hold a specific range of pressure and temperature. When something pushes past that range a fire, a control failure, a blocked outlet, a runaway refrigeration cycle the vessel needs a way to protect itself before it protects nothing at all. That’s the job of the pressure relief valve (PRV). Why PRVs Matter So Much in Ammonia Service Anhydrous ammonia is stored and processed under pressure in refrigeration systems, storage tanks