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The whole installation: a worked boardDoes the total fit the supply fuse?

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The whole installation — a worked board

A domestic board whose protective devices total 130 A:

CircuitDevice
Ring final32 A
Kitchen ring32 A
Cooker32 A
Immersion heater16 A
Lighting, upstairs6 A
Lighting, downstairs6 A
Smoke alarms6 A
Total130 A
✋130 A on a 100 A supply fuse. Without diversity that is an overload — and it would not announce itself. A modest overload on a PILC supply cable takes a very long time to show: weeks or months, not minutes. By then there is heat damage.

Which is why the supply is sized on maximum demand, not on the sum of the devices.

Are these standard circuits?

The question that decides which entry of Table A2 you use. On-Site Guide · Appendix H sets out the standard arrangements of final circuits. An ordinary domestic board is all standard circuits.

Table A2, item 9 — standard circuits

In On-Site Guide · Table A2, item 9 (p.152) is the “Standard arrangement of final circuits in accordance with Appendix H”. For a household installation it says:

100% of the largest circuit  +  40% of every other circuit
StepWorkingResult
Total of all protective devices130 A
Set aside the largest circuit at 100%one of the 32 A circuits32 A
What remains130 − 3298 A
40% of the remainder98 × 0.439.2 A
Maximum demand32 + 39.271.2 A
Which is the largest circuit? Here there were three at 32 A — the kitchen ring, the cooker and another ring. Where several tie, it does not matter which you pick.

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