Pressure measurement because atmospheric pressure is always changing and the reference in this case is fixed at 1 bar. To produce an absolute pressure sensor, the manufacturer seals a high vacuum behind the sensing diaphragm. If the process-pressure connection of an absolute-pressure transmitter is open to the air, it will read the actual barometric pressure. The SI unit for pressure is the pascal (Pa), equal to one newton per square metre (N·m or kg·m·s). This special name for the unit was added in 1971; before that, pressure in SI was expressed in units such as N·m. When indicated, the zero reference is
ISO 3166-2:PA ISO 3166-2:PA ISO 3166-2:PA is the entry for Panama in ISO 3166-2, part of the ISO 3166 standard published by the International Organization for Standardization (ISO), which defines codes for the names of the principal subdivisions (e.g., provinces or states) of all countries coded in ISO 3166-1. Currently for Panama, ISO 3166-2 codes are defined for 10 provinces and 3 indigenous regions. Each code consists of two parts, separated by a hyphen. The first part is , the ISO 3166-1 alpha-2 code of Panama. The second part is either of the following: The codes for the provinces are assigned in