At low power research reactors, in-service inspection (ISI) is usually carried out on components which are not directly accessible due to a high radiation level; such as the reactor tank, the core structure, fuel elements, etc. For these ISI inspections tools and methods have been developed based on experience in non-nuclear applications and modified or adapted to the nuclear environment. Some ISI methods that are used at some facilities are:

• reactor tank and shielding structure

• reactor safety system

• reactor cooling system

Once the systems have been defined each system has to be broken down into sub-systems or components, such as

• visual inspections using

  - underwater telescope

  - endoscopes

  - underwater cameras using radiation hardened systems

• replica method

Other non-radioactive components may be inspected with methods used in conventional industries. The following methods and tools are typically used in a TRIGA Mark-II reactor but may easily be adapted for any other low or even high-power research reactor.