An official in France 's Atomic Energy Commission reported that they estimated the blast was " about or less than a kiloton " and expressed uncertainty about whether or not the blast was actually nuclear . There have been various large planned and unplanned non-nuclear explosions comparable in yield to small nuclear detonations , such as the U.S. " Minor Scale " explosion from 1985 , which used conventional explosives to simulate a 4 kiloton detonation . According to the '' Washington Times '' anonymous U.S. intelligence sources speculated there " was a seismic event that registered about 4 on the Richter scale , but it still is n't clear if it was a nuclear test . You can get that kind of seismic reading from high explosives " . '' The Wall Street Journal '' explains that this blast was equivalent to the explosive force of about US$ 100,000 worth of ammonium nitrate . International experts have said that it will take some time to confirm whether it was a successful nuclear test , as North Korea claimed , or an unsuccessful one ( " fizzle " ) , or perhaps not even a nuclear test at all
Minor Scale
Minor Scale
2006 North Korean nuclear test