Corneal Ulcer Guide: 1  Definition. 2  Causes & Prevention. 3  Diagnosis and Tests. 4  Symptoms and Signs. 5  Treatment & Prognosis. >>> 6  Dog Health A-Z.
Standard Temperature and Pressure (STP) Standard Temperature and Pressure (STP) is defined as 0 degrees Celsius and 1 atmosphere of pressure. Do not confuse STP with the STP Products Company, a maker of oil and fuel additives...unless you are reading one of their MSDS's!
A barometer measures atmospheric pressure. It is measured in various units, one of the oldest being inches of mercury. Other units include pounds per square inch (PSI) kilo-Pascals (kPa) and atmospheres (ATM). Standard pressure is 29.92 inches of mercury, 14.7 PSI, 100 kPa or 1 ATM. Lower barometer readings are generally associated with less stable weather (as in, low pressure system), while higher ones are generally associated with more stable weather (as in, high pressure system).