Fire Exits in pubs

Check out the http://www.environ.ie/en/Publications/DevelopmentandHousing/BuildingStandards/FileDownLoad,1640,en.pdf (Part B Fire Regs) - section 1.4.3.2
 
The exits I'm talking about are not ulitmate exits into the street, and so they (b) rather than (a) exits [possible that the OPs exit is a (b) - may lead into corridor or other area before final exit?]. The question is whether or not you regard a push button to open a mag lock as being as a "simple fastening"?

My personal opinion, not being a fire expert, is that I'd rather press a simple push button than turn a handle or unlock a fastening - a lot quicker and idiot proof. One big advantage of the mag lock is that there is no bolt or whatever you call the thing which goes into the door frame, so there is no possibility of it jaming/getting stuck.
 

Well the one in the pub that I'm referring to opens onto the street. And there didn't seem to be any button or anything!