Shut-in Pressure 2 : The pressure at a datum when the well is not flowing. The shut in pressure is usually either surface shut-in pressure or bottom hole shut-in pressure
George E. King Engineering, 5000 Oilfield Terms: A Glossary of Petroleum Engineering Terms, Abbreviations and Acronyms, US 2010. http://gekengineering.com/Downloads/Free_Downloads /Glossary_of_Petroleum_Engineering_Terms_25_August _2010.pdf, (Oil - Amer) {593}