Furnace refractory lining is the protective layering in the furnaces that allows them to operate at high temperatures allowing for efficient metal smelting over extended periods of time. Over time, this lining deteriorates due to intense process conditions, causing problems for the furnace’s performance and efficiency. The wear of refractory linings in metallurgical furnaces can result in various failure modes, such as metal leaks due to gaps in the refractory lining, run out due to refractory thinning, run out due to metal penetration, and sidewall collapse due to thinning of load-bearing refractory. Hence, to protect the asset it is crucial to monitor the furnace’s refractory conditions. However, this requires a multivariable system setup that includes initial design parameters, baseline measurements, and follow-up risk-based inspections and monitoring. Utilizing technologies such as fiber optics, thermocouples, AU-E, and acoustic emissions in combination with frequent audits and physical measurements has proven effective in monitoring refractory wear and gap formation, detecting chemical attacks within the lining and preventing leaks and run outs, and minimizing furnace downtime and even contribution to the extension of furnace campaign life. In this paper, we discuss the cause and effect of refractory wear and the combination use of technologies to inspect and monitor furnace lining and crucible.