encompass compounds that have the capacity to inactivate the enzyme acetylcholinesterase (AChE); divided into 2 families, the G agents and the V agents; G agents (tabun, sarin, soman cyclosarin) are volatile compounds that pose mainly an inhalation hazard; V agents (VX, VE, VG, VM, V-gas) are persistent and remain on surfaces for long periods, the consistency of V agents is oily, thus mainly pose a contact hazard.