Editing Spirometry (section)

===Procedure===
The basic forced volume vital capacity (FVC) test varies slightly depending on the equipment used. It can be in the form of either closed or open circuit. Regardless of differences in testing procedure providers are recommended to follow the [https://www.thoracic.org/statements/resources/pfet/PFT2.pdf ATS/ERS Standardisation of Spirometry]. The standard procedure ensures an accurate and objectively collected set of data, based on a common reference, to reduce incompatibility of the results when shared across differing medical groups.

The patient is asked to put on soft nose clips to prevent air escape and a breathing sensor in their mouth forming an air tight seal. Guided by a technician, the patient is given step by step instructions to take an abrupt maximum effort inhale, followed by a maximum effort exhale lasting for a target of at least 6 seconds. When assessing possible [[upper airway obstruction]], the technician will direct the patient to make an additional rapid inhalation to complete the round. The timing of the second inhale can vary between persons depending on the length of the proceeding exhale. In some cases each round of test will be proceeded by a period of normal, gentle breathing for additional data.