Inspection of serpentine coils in fired heaters has historically been a challenge for the owner/operator due to limited physical access, especially within the convection section. Most conventional NDE approaches (i.e. manual ultrasonics) attempt to inspect from the coils exterior surface; however, access is typically limited to only the coils radiant section, leaving the convection portion of the coil uninspected. More importantly, conventional NDE is time consuming and the inspection coverage typically only encompasses 2-3% of the coil’s surface. Engineers attempting to carry out Fitness for Service (FFS) applying manually obtained inspection data results in a lot of guess work needed to fill in the information voids. Use of ultrasonic based intelligent pigging technology has eliminated these challenges. 100% inspection coverage of both the Convection and Radiant sections now provide engineers with a much higher lever confidence in the FFS analysis, ultimately allowing plants to operate the heaters longer and often at higher throughput.