This paper presents a modeling, simulation and experimentation for detection of material losses and deposited scales in boiler tube specimen by adopting Pulsed Thermography (PT). A data analysis approach, based on variations of slopes in Temperature-Time responses has been adopted, to estimate material losses and subsurface scale detection in the tubes. The slopes are calculated for different pixels in the field of view of the captured image sequence during transient heating cycle of the specimen. Relative thickness variations due to material loss and the deposited scales of boiler tube have been estimated from the calculated slopes. Experimental results are presented in support. Copyright © 2008 American Scientific Publishers. All rights reserved.