BS3621 – Removing the Mystery

We all feel for the man in the advert being quizzed about his locks, but, really, there is no mystery.

If your doors are fitted with mortice locks:

BS3621 Mortice Lock
BS3621 Mortice Lock

If your doors are fitted with nightlatches:

BS3621 Nighlatch
BS3621 Nightlatch

simply look at the edge of the door where, if your locks are BS3621 standard locks, you will see the Kitemark

BS3621 Kitemark
BS3621 Kitemark

Why Should I Care?

BS3621 is a lock standard by British Standards Institute (BSI) for thief-resistant locks. BS-3621 locks are found on some front and back doors in the home and it’s a good way to check that your security is up to standard. This is why some insurance companies require door locks are fitted to BS 3621 British Standard.

BS 3621 is the original lock standard and was first introduced in the 1960’s, the key facts you need to know about BS3621 locks are as follows:

  • Usually found on wooden & timber doors in domestic homes, but can appear on metal doors in commercial premises.
  • A key is used for opening or exiting the lock – also known as the term ‘keyed egress’.
  • Cannot be opened on either side unless you have the key.

The main benefits of having BS3621 British Standard approved locks fitted are:

  • Tested against Burglary techniques such as drilling and picking
  • Comply with your insurance policy – most require this standard as a bare minimum

For a lock to meet British Standard BS3621 it must have:

  • 5 levers having at least a 1000 key differs
  • Measures to prevent picking those 5 Levers
  • Anti-pick qualities
  • Hardplates to protect the lock from drilling
  • Minimum of 20mm bolt throw into the door frame

Some insurers may insist your locks have to meet BS3621, other insurers may not have that exact requirement, so it’s down the individual to check with their insurer regarding any standard your locks should meet.

Master Lock and Safe Ltd supply and fit BS3621 locks.
They are also available from our website.

Mortice Locks – Click Here

Nightlatches – Click Here

Euro Cylinders are covered by a different rating system which we will be looking at in our next blogpost.

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