Background and Aims: The estimation of standard spirometric measurements needs to measure a participant’s non-mutated standing height. Even so, as a direct consequence of physical impairment, traumatic amputation, as well as other structural deformities or neuromuscular disablement, a few patients referred for lung function assessment cannot stand. Materials and methods: The study involved 202 participants and consist of two elements that are data collection and data analysis. There were four types of data: standing height measurement, arm span measurement, sitting height measurement and predicted pulmonary function, including forced vital capacity (FVC) and forced expiratory volume (FEV1), which was studied based on correlational analysis. Results: The study shows a positive, linear solid correlation between arm span and standing height measure in centimetre with an R-value of 0.919. There is a positive moderate linear correlation between arm span and sitting height measure in centimetre with an R-value of 0.604. Sitting height and standing height has a positive, strong linear correlation with an R-value of 0.744. For the pulmonary function test, a positive, strong linear correlation between Forced Vital Capacity prediction using sitting height and Forced Vital Capacity prediction using standing height with an R-value of 0.710. There was a positive moderate linear correlation between Forced Expiratory Volume prediction using sitting height and Forced Expiratory Volume prediction using standing height with an R-value of 0.577. The relationship between forced vital capacity and forced expiratory volume predicted value of a pulmonary function using arm span and forced vital capacity with forced expiratory volume predicted value of a pulmonary function using standing height shows a positive, strong linear correlation with forced vital capacity R-value of pulmonary function 0.950 and forced expiratory volume R-value of 0.938. Conclusion: Overall, based on the obtained results of the study, it has been proven that the arm span measurement would be the most compatible alternative measure to be used instead of standing height in the case of a patient with permanent disability or incapacitated for clinical purposes and pulmonary function test compared to sitting height.