The only regulations for UK CAA regarding evacuations are that the cabin crew have been trained in methods of evacuation by an authorised body (ie via facilities offered by another airline if they do not have approved facilities themselves), and tested on knowledge and understanding of drills and procedures in place.
Also that cabin crew maintain 'recency' (recency applies to all aspects of aviation from crew to engineering), to ensure they are familiar with the aircraft they are working with, and also to receive refresher training on an annual basis, to include testing.
Pre-flight briefings should be conducted to check all crews have current knowledge of safety equipment & emergency procedures and aviation medicine.
Any amendments to the orders must be approved by the CAA and notified to crew as a RN (Red Notice).
All drills, equipment, procedures and regulations, etc must be in writing as orders, agreed by the CAA and fit in with their legislation.
CFG - Check your PMs!
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