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British Standard Locks: What are they?

Its no secret that unless you are in the home security industry the chances are you know very little about lock standards, particularly, BS3621. If you know just the basics this can be very useful! Lock standards are in place so that you can be sure that when you have had a British standard locks fitted it has been thoroughly tested to meet certain security criteria. British standard locks make your property much more secure and can even act as a deterrent to potential burglars.

Another benefit of British standard locks is that having them installed can also reduce your insurance premiums, also, if you don’t have British standard locks installed and your home is broken into your insurance policy could be invalid and your insurer may refuse to pay out on any claims.

What are British Standards?

Standards are the agreed best way of doing something or of meeting specific criteria. Standards are created by a collaboration of experts, academics, users, manufacturers etc. These groups come together and share knowledge and best practice.

This is then written into a document known as a Standard. British Standards exist across many technologies and industries. Compliance to any particular BS is an indication that specifically defined criteria have been met. Here is the best Emergency Locksmiths York services you can check now.

What Is BS3621?

BS 3621 was introduced in 2007 and is the British Standard for:

‘Lock assemblies operated by key from both the inside and outside of the door.’

This standard applies to:

• Mortice Deadlocks & SashLock

• Euro DeadLocks & SashLocks

• Cylinder locks e.g. Nightlatches and rim cylinders

For a lock to be in compliance with BS3621 it must meet specific design and functionality criteria. For example, the lock must have 5 levers, be able to withstand a drill attack for up to 5 minutes, have an anti-picking mechanism and have specified minimum bolt length etc. Locks that meet these standards are considered “good thief resistant locks”.

Do All Exterior Door Locks Need To Be BS3621?

This much depends on the type of property. Locks that meet this standard should be fitted to appropriate external doors such as wooden or timber doors. These locks provide optimal security at affordable prices.

The exception to this is that they are not suitable for use on common main door exits on flats or apartments. A lock with a key on the outside and a thumbwheel on the inside is more appropriate. This allows emergency exit for all households without the use of a key (this type of lock should conform to BS8621).

How Can I Tell If My Lock Is BS3621?

Once a lock has been through rigorous testing and meets the security and safety criteria it will be awarded a kitemark from the BSI for the particular lock design and manufacture. The BSI Kitemark is one of the most recognised symbols for indicating quality, reliability, and trust.

If a lock conforms to BS3621 the kitemark and standard reference should be stamped on the face of the lock. This will be visible when the door is open and is also prominent on the packaging material.

Do insurance companies require locks to be BS3621?

Every insurance company will have its own requirements, however, in most cases there is a requirement for locks to comply with BS3621. As mentioned earlier, if you inadvertently indicate that your locks are of this standard and subsequently this is shown not to be the case, your insurance provider may reject any future claims. Here is the best Locksmith Leeds Services you can check now.

Are There Other Lock Standards?

Yes, there are other lock standards specific to different lock types. Some of the most common include:

TS007 3 Star

This is an up to date and improved version of the Kitemark for cylinder locks, commonly found on uPVC and composite doors. It was developed by the Door and Hardware Federation and the Glass and Glazing Federation.

This update was developed specifically in response to criminals using bespoke methods such as lock snapping to specifically attack lock cylinders. It provides several layers of protection.


Lock assemblies operated by a key from the outside of the door and by handle or thumb turn from the inside of the door’

As noted earlier, the BS8621 standard is relevant to locks that need a key for entry but not for exit. These are most often seen on main door exits in blocks of flats. They operate with a key on the outside of the door and a thumb turn on the inside. This type of lock enables emergency escape without the need for a key.


Lock assemblies in which the operating mode can be switched between the normal BS8621operating mode and a secure mode in which no egress is possible’

Locks to this standard provide all the security and functionality of BS8621 locks with the additional capability to manipulate the key from the outside to disable the interior escape functions (thumbwheel/thumb turn.

For Example, if you were the last person to leave a building you can lock up and disable the escape function, so, if for example, somebody broke in through a window, they could not escape via the door.

If you need your locks upgrading to locks the meet the British Standard then contact Dr Locks Ltd today – 01904 295 465

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