I spoke to an electrician who worked in prisons and he said he had never seen so many unusual sizes of MCBs until he opened a board in a prison as they have very close circuit protection.

Botany Bay perhaps?

There’s oddities such as 9.17 amp MCBs

https://uk.rs-online.com/web/p/mcbs/2103399

Used to see 7 amp in Zimbabwe, usually on military accommodation married quarters on the un metered incomer, 7 was yer lot, lights, hot water,no heating as such

Without space heating, 7 amps is fine.

A 1 kw or 1.2 kw water heater, with a changeover switch to permit use of a kettle or toaster instead. 6 lamps, mixed wattages, a couple of fans and a radio would be fine with sensible use of the lights, not all on at once.

Could probably supply a fridge if care was taken. A forty watt fluorescent lamp with power factor correction would give a better light than a 100 watt incandescent bulb.

AFAIR cooking was done on a paraffin or wood burner, these were new builds in the 90s

Single guys presumably were allowed 2 amps each with shared bathrooms, etc.

Sparkingchip: 
 

There’s oddities such as 9.17 amp MCBs

https://uk.rs-online.com/web/p/mcbs/2103399

Looks to me like an ordinary 10A nominal device … but someone has copied the wrong number from the data sheet (9.17A is the rating for 40 degree ambient rather than the usual 30 degree).

   - Andy.

AJJewsbury: 
 

Sparkingchip: 
 

There’s oddities such as 9.17 amp MCBs

https://uk.rs-online.com/web/p/mcbs/2103399

Looks to me like an ordinary 10A nominal device … but someone has copied the wrong number from the data sheet (9.17A is the rating for 40 degree ambient rather than the usual 30 degree).

   - Andy.

Annnnnnnnnnnd the image shows a 16 Amp device.

Z.

Annnnnnnnnnnd the image shows a 16 Amp device.]

Yes, unfortunately that's typical of RS - “image indicative of range” is what they usually say…

   - Andy.