EU OPS 1.1235 states:-
"An operator shall ensure that all appropriate personnel are familiar, and comply, with the relevant requirements of the national security programmes of the State of the operator."
and 1.1255(c) states:
"In all aeroplanes which are equipped with a flight crew compartment door in accordance with subparagraph (b):
1. this door shall be closed prior to engine start for take-off and will be locked when required by security procedure or the commander, until engine shut down after landing, except when deemed necessary for authorised persons to access or egress in compliance with National Aviation Security Programme; (NASP)"
The UK NASP has since been superseded:
This initiative led to the adoption of framework Regulation (EC) No 2320/2002 of the European Parliament and of the Council of 16 December 2002 establishing common rules in the field of civil aviation security and thus provided the basis for allowing harmonisation of aviation security rules across the European Union with binding effect.
That regulatory framework has since been overhauled by a new framework, in full effect from 29 April 2010, as laid down by Regulation (EC) No 300/2008 of the European Parliament and of the Council of 11 March 2008 on common rules in the field of civil aviation security and repealing Regulation (EC) No 2320/2002 which states:
10. IN-FLIGHT SECURITY MEASURES
1. Without prejudice to the applicable aviation safety rules:
(a) unauthorised persons shall be prevented from entering the flight crew compartment during a flight;