In Iraq, forensic analysis of evidence from IED (improvised explosive device) attacks has produced some interesting results. Most IEDs are locally made, in secret workshops. As a result, there are not any standard plans. So the products of different workshops can often be identified. As a result, it is possible to plot the "distribution pattern" of attacks by IEDs made in a particular shop. Reportedly this has been useful in locating some of the bomb factories. Another way that bomb factories are discovered is by chance, when one blows up accidentally. Since safety standards and working conditions are primitive, there have reportedly been a number of explosions in IED factories.