The paper reports the use of pulsed laser based photoacoustic (PA) pyro analysis technique to study the thermal decomposition, stability and acoustic fingerprints of nitro rich phenyl and benzyl triazole derivatives. Two compounds named as 1-(3-methoxy-2,6-dinitrophenyl) -1H-1,2,3-triazole (S-10) and 1(4-methoxy-3,5-dinitrobenzyl)-1H-1,2,3-triazole (S-4) are studied using visible 532 nm and UV 266 nm wavelengths, respectively, obtained from Q-switched Nd:YAG laser of 7 ns pulse duration and repetition rate 10 Hz. These compounds are also subjected to the thermo gravimetric-differential thermal analysis (TG-DTA) technique. The obtained results of pulsed PA and TG-DTA techniques are used to understand the thermal stability and decomposition mechanism of HEMs. We have also evaluated the thermal quality factor 'Q! which plays very important role to test the thermal stability of the S-4 and S-10 irrespective of incident laser wavelengths. (C) 2015 Elsevier B.V. All rights reserved.