According to the market reports, the global photonic sensor market is predicted to have a quantum shift over the next few years. This surge in demand can be attributed to factors such as innovation in the field of fibre optics and expanding the spectral use of sensors in varied industries. The growth of the Fibre Bragg grating (FBG) sensors is one of the most exciting developments in the field of fibre optic sensors in recent years. Compared with conventional fibre-optic sensors, FBG sensors have a number of distinguishing advantages, which makes it a popular choice among many industries. The researchers at the City, University of London (CITY UL) have explored this technology extensively to produce a number of FBG-based sensors, including humidity and temperature sensors, which have been recognized by a number of industrial sectors.