If two firecrackers produce a sound level of 95 dB when fired simultaneously at a certain place, what will be the sound level if only one is exploded? [Hint: Add intensities, not dB Solution 95 = 10 log [ I / (1e-12) ] I = 3.16 e-3 internisity for one , I = 3.16 e -3 / 2 = dB = 10 log [ 3.16e-3 /2 *1e-12 ] dB = 91.989 dB.