Are key lockable device allowed on fire rated and non fire rated doors within a shop if the key is present or do these require replacing to thumbturn mechanisms?

When the premises is occupied all doors required for means of escape, the handle shall release a door at all times in the direction of escape, when the premises are occupied, in less than 1s, by one single hand operation only  and not require the use of a key or other similar object. It should enable immediate exit from the inside at all times regardless of any additional locking such as a deadbolt or outside access device.

Check out http://firecode.org.uk/Code_of_Practice_hardware_for_fire_and_escape_doors.pdf

 

Simple answer - no if it is required as a means of escape.

Will a site specific risk assessment allow the use of key locked emergency exits in specific types of premises? Some residential and secure units are allowed key locked exits if management controls are in place.

In my opinion you can have locked fire exit doors on certain specific types of premises, providing you have a manual override facility. I accepted glass bolts supported by an intruder alarm on a bonded warehouse, many moons ago, but that is not the norm. Nowadays I hear about management controls quite often but I am afraid I am very sceptical, considering the list of priorities for management, I believe fire safety comes way down the list but many FR assessors do accept it. 

Check out http://www.firesafe.org.uk/security-and-fire-safety/

No unless you are a very specific sector such as prisons. They have contributed to too many deaths over the years, even when the key has been attached to the door in a glass fronted box.

There are plenty of other solutions available now, the nearest you could get is the Emergency Fastening (Frangible) from Imperial Locks http://www.imperiallocks.co.uk/fire.htm