BS 3621

BS 3621:2017 + A2:2012 – Thief Resistant Locks (Key Egress)
Lock functions and applications:
Since its inception, BS 3621 has always required security from both sides, meaning that, once locked, a key is always required to open the door, whether from the inside or the outside. Recognising that there are situations in which a keyless egress lock (secure only from the outside) can offer acceptable security, as well as safety benefits.
Standard |
Function |
Comments |
BS 3621 |
Locked by key from both sides |
Provided that the key is removed, this type of lock is secure against operation by intruders reaching through a letter-plate, breaking nearby glazing etc. Best used where emergency escape is not required or where other means of escape exist. |
Sources:
Door and Hardware Federation (DHF) Best Practise Guide: BS 3621:2007 Thief resistant locks assemblies – Key egress