Isolation of smoke alarms?

[Asm]

So i've spent most of today with my head in my hands whilst attempting course work. Long story short i stumbled across section B1.19 of the Building Regulations which states:

'The mains supply to the smoke alarm(s) should comprise a single independent circuit at the dwellinghouse's main distribution board (consumer unit) or a single regularly used local lighting circuit. This has the the advantage that the circuit is unlikely to be disconnected for any prolonged period. There should be means of isolating power to the smoke alarms without isolating the lighting.'

My question is what is deemed as suitable means of isolating the smoke alarms without isolating the lights if they share an MCB?

 

[telectrix]

Fcu??? (unswitched)

 

[tazz]

All mains powered smoke alarms comply by the base forming the isolation, and lockable by means of using a tool, such as a srewdriver. Therefore using a srewdriver you can remove the detector, and thus isolating the unit. complies with BS 5839 and document B

 

[tazz]

ASM under the trainee section, please feel free to ask any questions you may have, as there are many categories of fire alarms. All with different isolation standards. We are here to help with your continued training....