A Cone Calorimeter device has been used to measure the flammability properties of samples with different clay dispersion on the nanometer (molecular) scale. Specifically, chemical energy release rate, mass loss rate, and time to ignite (melt and char also) are measured. Samples consisting of pure Nylon 6 and Nylon with nano-clay additives up to 5 % are used in the study. In addition, the effect of thickness is considered for 1 to 24 mm. Data obtained over a range of radiant heat flux are analyzed to illustrate the effect of clay loading and thickness on heat of combustion, heat of gasification and ignition temperature.