Digit 7 – Security
Four grades are identified:
Grade 0: not approved for use on burglary resistant doors
Grade 1: mild burglary resistance
Grade 2: moderate burglary resistance
Grade 3: high burglary resistance
Grade 4: extra high burglary resistance

 The main requirements include resistance to drilling, close fitting plates or escutcheons to help protect the lock and support the cylinder. They must be resistant to removal from the outside of the door and make provision to minimise the cylinder projection to a maximum of 3 mm. Full details of the requirements can be found in BS EN 1906:2012.