Section 5 can be tested by asking, for any proposed basis of intervention, whether a specific provision of the Act actually authorises it, and whether that provision, not something else, is what is being relied upon.
Applying the test:
Party consent to supervision, an unspecified procedural irregularity, and a court's own view that the award seems unjust on facts are none of them grounded in any specific enabling provision of Part I. They rely instead on agreement, generality, or subjective judgment, none of which Section 5 recognises as sufficient.
Conclusion:
Only intervention that traces back to an express provision within the Act, such as the sections governing interim measures or challenges to an award, satisfies the test Section 5 sets up.
Section 5 exists to preserve arbitration as a genuinely private, self-contained dispute resolution process, keeping courts out unless the statute itself opens a specific door. Testing each option against that purpose of minimal, textually-anchored intervention shows which one actually fits.
Only intervention rooted in the Act's own express provisions actually respects the purpose of minimal judicial interference that Section 5 was written to protect.
Therefore, the correct answer is When the Act expressly permits such intervention.