In this research, the authors introduce a photonic crystal fiber (PCF) sensor for precise identification of Hydrogen Cyanide (HCN) along with Sulphur Dioxide (SO2) that exhibits an exceptional performance. The authors obtain maximum Relative Sensitivity (RS) of 97.23% and 99.19% for HCN and SO2, respectively, at the operating point of 2.8 THz by introducing a sensor. The sensor has a pigmy Confinement Loss (CL), Total Loss (TL) along with Effective Area (Aeff) such as \(1.285\times {10}^{-3}\) dB/m and \(9.825\times {10}^{-6}\) dB/m for CL, \(5.002\times {10}^{-3}\) dB/m and \(2.107\times {10}^{-3}\) dB/m for TL along with Aeff of \(5.577\times {10}^{-8}\) m2 and \(5.120\times {10}^{-8}\) m2 for HCN and SO2 respectively. SO₂ and HCN are exceedingly harmful gases that have detrimental effects on the environment and human health. By blocking cytochrome oxidase, the colorless and volatile substance HCN impairs cellular respiration and causes cellular asphyxia. Death, brain injury, or respiratory distress can result from even low doses. A strong gas called SO₂ irritates the respiratory system, making bronchitis, asthma, and other pulmonary conditions worse. Long-term exposure raises the risk of cardiovascular disease and damages lung function. Both gases are hazardous to the environment. SO₂ damages ecosystems and infrastructure by causing acid rain and air pollution. With the implementation of the PCF sensor, we can reduce our health risks and secure our environment from those lethal gases.
