The by-poll elections are falling on Sept 17, and 220 polling stations and 573 polling booths have been formed for the purpose.
The presiding officers and polling staff will initiate the training program from September 6, the RO revealed.
Pakistan Muslim League-Nawaz (PMLN) nominated Kulsoom Nawaz, Pakistan Tehreek-e-Insaf has Dr Yasmin Rashid, and Pakistan People’s Party (PPP) nominated Faisal Meer.
It was decided, in a meeting chaired by Chief Election Commissioner Justice (retd) Sardar Raza Khan on Friday that the ECP would be using, as a test case, biometric machines in the NA-120 by-poll.
There are 321,786 registered voters in the constituency, the ECP stated.
Earlier, the NA-120 seat fell vacant after disqualification of Nawaz Sharif by the Supreme Court the in the Panama Papers case on July 28