The COVID-19 pandemic, which first emerged in Wuhan province, China, in 2019, resulted in an unprecedented global demand for medical oxygen. In India, the need for oxygen surged dramatically in 2020 as COVID-19 cases escalated. To this sudden demand, various solutions were implemented, including the installation of oxygen generators in hospitals, the transportation of medical and industrial liquid oxygen, and the use of oxygen cylinders and concentrators. Unlike cylinders that require refilling, oxygen concentrators can provide a continuous supply of medical-grade oxygen, given that there is a reliable power source. They offer significant benefits for patients in the early stages of illness or following COVID-19 treatment, as they can be used in various locations. This paper aims to examine oxygen concentrators that utilize the Pressure Swing Adsorption (PSA) method for oxygen separation. Furthermore, this paper reviews developments in techniques for oxygen concentration to inform readers. This study seeks to enhance the availability of oxygen concentrators to meet local demand during emergencies.