"As little as one or two kilograms of biological agent dispensed with a commercial crop sprayer can cause devastating results. It would take substantially more chemical agents to have the same effects. However, in quantities of 50 to 150 kilograms (well within the carrying capability of many low cost UAVs), chemical agents can be very deadly. The research also shows that both chemical and biological weapons are relatively easy to obtain and do not require great technical knowledge to produce, store, or use. Nuclear weapons, on the other hand, present greater challenges for employment on UAVs. Acquiring a complete nuclear weapon or the material and technology to fabricate one is extremely difficult and expensive. Additionally, the size and weight requirements for even a small weapon (about 200 kilograms) is right on the edge of the payload capability of all but the most capable and expensive UAVs."