In Pete's World, the Preachers possessed electromagnetic bombs created by Angela Price that were used to destroy computers. Using one on a Cyberman had the effect of crippling it and disabling its emotional inhibitor. (TV: The Age of Steel) An EMP device was used when the Preachers attacked the Cybus factory in Paris. (GAME: Save Paris)
Since Bannakaffalatta was a cyborg, his body contained a device capable of emitting an EMP which would temporarily shut down Heavenly Hosts. In generating the electromagnetic pulse, Bannakaffalatta drained almost all his power, dying shortly thereafter. However, Mr Copper, Astrid Peth and Rickston Slade were able to obtain the EMP device, recharged it, and used it as a weapon against other Hosts.
Mr Copper also used to sell EMP transmitters on Sto to the discriminated cyborgs, reminiscing, "They'd always give me a bed for the night in the cyborg caravans. They're good people." (TV: Voyage of the Damned)
A type of EM pulse known as an "EM theta pulse" destroyed biomatter. On the colony ship Amandala, engineer Mikhail, acting on the Eighth Doctor's advice, shunted the energy from the ship's damaged reactor core through the plasma streaming, causing it to react with the shield harmonics and creating an EM theta pulse which killed everyone on board except the Doctor and Mikhail. (PROSE: Reversal of Fortune)