An electromagnetic pulse (also known as EMP) is a pulse of electromagnetic radiation emitted by certain devices that can render the technology of some races inert, albeit temporarily. On Earth, EMP was discovered by accident. Besides the Tau'ri, other races are known to have used EMP. All Ancient technology is apparently impervious to EMP. (ATL: "The Siege, Part 3")
EMP was used a fair number of times over the years.
- An EMP was launched into the event horizon of an incoming Stargate using an EMP Generator in the hopes of stopping Anubis' Stargate destroyer, but the device was only damaged in the process. (SG1: "Redemption, Part 2")
- Caius' Tel'tak was equipped with EMP. Vala Mal Doran used the device to override the systems on Lucian Alliance Al'kesh vessels, so that they could escape. (SG1: "The Ties That Bind")
- An F-302 fighter-interceptor discharges EMP due to a concussive force interfering with the artificial gravity field generated by the inertial dampeners. They used that technique to shut down the electronic systems in the Rand Protectorate building. (SG1: "Ethon")
- An overloaded Naquadah generator, when detonated releases a massive pulse of EM energy. The Atlantis expedition used that technique in combating a nanite outbreak in Atlantis. (ATL: "Hot Zone")