Precise pressure measurement in the range 0.1–500 torr

摘要: Abstract It is becoming increasingly important in several fields of work to make precision measurements the pressure ultra pure gases range 0.1–500 torr and above. To cater for this need commercial gauges have been developed over last decade. Two these gauges, a quartz high gauge, capacitance manometer are discussed, their performance limitations discussed. A “dead-weight” primary standard, which has used as sub-standard checking absolute accuracy instruments, also described. will be shown that, although lacks resolution at pressures less than 4 torr, it general stable long periods time. By contrast, possesses extremely low pressures, but appears lack term stability expected instrument.