of course they also mean unless you have the key for the tag you can't reset them either.ColJack said:you can get tags for some breakers that make it so you cannot turn the breaker off, they still trip if needed..
so in a household situation the householder would have to have they key and therefore be able to turn off the smoke alarms if they want.
not much point imo unless you have small mischevious kids and in that case i think you'd do better to restrict access to the CU as a whole rather than one breaker.