Final answer:
When a fault can be repaired on the spot, it should be addressed immediately using proper tools and safety precautions, with the process and repair documented for future reference.
Step-by-step explanation:
If a fault can be repaired on the spot, it is generally best to address it immediately to prevent further issues.
Quick and effective troubleshooting and repair can minimize downtime and potential safety hazards. In the context of engineering, for example, identifying the problem, consulting the necessary documentation or instructions, using the correct tools, and taking precautions for safety are all important steps in the repair process.
Moreover, documenting the fault and the repair is crucial for future reference and for understanding the reliability of the system or equipment involved.