ISPH Nuclear Energy Practice Test 2026 – Complete Exam Preparation

Coolant chemistry defines the chemical environment inside the reactor’s cooling loop, and that environment directly controls how metals corrode, how corrosion products deposit as CRUD on surfaces, and how those products become activated and contribute to radiation fields. Corrosion weakens components over time; CRUD deposits on fuel and heat-transfer surfaces reduce heat transfer and can affect reactor efficiency and safety. Activated corrosion products become a source of radiation, increasing dose rates and complicating maintenance and cleanup. The common control measures focus on keeping the water chemistry in a range that minimizes corrosion and CRUD while also managing reactivity. pH control is key because a stable, slightly alkaline environment reduces corrosion rates and helps form protective oxide films. Zinc injection helps by forming protective surfaces and suppressing CRUD formation and activation of corrosion products. Lithium and boron are used to manage pH and reactivity: lithium keeps the coolant pH stable with minimal corrosion risk, while boron acts as a neutron absorber to tune reactivity, all part of keeping both the materials condition and reactor power behavior favorable.