what is the relative pressure in albuquerque
In a barometer, the Bourdon tube is sealed at both ends and the absolute pressure of the ambient atmosphere is sensed. The Bourdon pressure gauge measures pressure relative to atmospheric pressure, that is, they measure presure directly relative to the surrounding atmospherice pressure. For example, Albuquerque New Mexico at our facility is at 5,000 feet above sea level with an atmospherice pressure of 630 mmHg. A bourdon gauge calibrated at sea level (760 mmHg) would read about 5 inHg of vacuum at our location.