NPCIL selects Scientific Assistants through a written test (CBT) followed by a document verification and medical examination. The written test includes Technical Subject questions, General Science with Nuclear Basics, and General Awareness. There is no interview for Scientific Assistant-C posts. Candidates who clear the written test merit list are called for document verification at the respective plant site. Medical fitness standards for nuclear facility work are stringent.

NPCIL Scientific Assistants are placed in the SA/C grade with a starting pay of approximately Rs. 21,700 per month under the IDA pay scale. The total CTC including Nuclear/Field Allowance, HRA, and other allowances reaches approximately Rs. 4–6 lakh per annum. Employees working inside the controlled area of nuclear plants receive additional Nuclear Allowance. The pay scale is revised every five years as per DPE/NPCIL Board approval.

The Nuclear Science Basics section tests fundamental concepts including radioactivity, types of radiation (alpha, beta, gamma, neutron), nuclear fission and fusion, reactor types (PHWR/BWR/PWR), radiation protection principles, nuclear waste management, and safety culture. Candidates need not be nuclear engineering graduates — basic understanding from a physics background is sufficient. NPCIL provides internal training after joining to develop job-specific nuclear knowledge.

NPCIL Scientific Assistants are required to serve a bond period of two years. The bond amount is approximately Rs. 50,000 to Rs. 1 lakh and is forfeited or recovered if the candidate leaves before completion. Postings are at NPCIL plant sites across India, including Tarapur, Rawatbhata, Narora, Kakrapar, Kaiga, Kudankulam, and upcoming project sites. Since nuclear plants are mostly in semi-urban or rural areas, candidates should be prepared for a non-metropolitan work environment.

NPCIL Scientific Assistants can grow through internal promotion to Scientific Officer (SO/C, SO/D, SO/E, SO/F, SO/G) by appearing for departmental tests and through seniority-based promotions. NPCIL also offers lateral movement to administrative and corporate roles. The organisation sponsors GATE-qualified employees for B.Tech/M.Tech programmes. Career growth in NPCIL is steady and offers job security with government-equivalent benefits, including CGHS medical coverage.