1) See BS7273-4, ADB and other guidance. The default is all three (green double pole isolator, fire alarm link & fail safe on power loss) unless an FRA can justify why a departure doesn't compromise safety (there are specialist situations where this can occur.
There is a separate debate at the moment about the whole 'legality' of maglocks on exit routes at all due to issues with damage to fire doors invalidating certification & potentially performance, reducing safe head height with an obstruction and not being mechanical devices to BSEN179 or BSEN1125 (with suitable alternative electronic access control devices incorporating mechanical elements so they do now available)
2)That might be correct from a Building Regulations point of view but certainly isn't from a Fire Safety Law point if view - the statutory bar went out with the Fire Precautions Act and several premises frozen in time by fire certificates first issued in the 70's (or 60's under even older legislation) had some catching up to do after 2005. That's not to say all changes in approach from the past have to be changed, only those where the difference in approach/technology between then and now leads to an unacceptable risk to the safety of occupants as determined by the FRA. Just because someone said it was OK in the past doesn't make it so now - whilst some technology and standards from the past still can provide adequate protection others have been found to be sadly lacking, sometimes fatally so.
