No idea how the science on this works, but Patus has released a product called OdorScreen that "alters the perception of burnt flesh, decomposing flesh, infected wounds, vomit and other offensive bodily fluids or tissues" without masking other odors. Targetted at emergency, medical and military personnel, this allows your typical soldier, for example, to avoid puking upon entering a room filled with dead bodies, and yet still be able to smell a gas leak.