BS 3621 and EN 1303:2005
BS 3621 is a British Standard relating to thief-resistant locks.
EN 1303:2005 is a European Norm relating to cylinders.
Together, these standards benchmark for locks and cylinders on any external or entrance doors of any property to be acceptable to the "Association of British Insurers" (ABI).
Please note: These standards only guarantee the resistance of the locks and not the door to which they are fitted; therefore the effectiveness of any lock also depends on the quality of the door, frame, and other hardware (that is not tested to this standard), which may fail before the lock or cylinder.
European Norms (EN)
A European Norm (EN) is a another standard that outlines the rules of security, guidelines or characteristics required for products, services or systems, and has been adopted by one of the three recognised European Standardisation Organisations (ESOs): CEN, CENELEC or ETSI.
Products successfully tested against the benchmarks set by EN in the relevant standard are said to “comply with the requirements of the standard”, and will be accordingly marked on the packaging and often on the products themselves.
The security of a lock can't be determined visually, the standards are often marked on the products.
Some insurance providers if not most will insist their customers have British Standard locks installed on all exit doors, be it front door or back door to be eligible for cover.
Euro cylinder usually fitted to a uPVC or composite doors and Rim locks installed with nightlatch on wooden door.
The kit mark is usually placed on the side plate where the bolt comes out, visible when door is open.
You can see the kit mark on the faceplate and it is clearly visible when the door is open (faceplace held by two screws)
BS3621 ⁄ BS8621 ⁄ BS10621 - What Does It Mean?
BS3621 - The standard is relevant to mortice and cylinder rim locks. Lock assemblies operated by key from both the inside and outside of the door.
BS8621 - is a new standard and not so popular to the masses, however it has some distinct advantages for the domestic house and commercial applications. It has the ability to be operated without the use of a key. This is ideal for fire exit or places where quick exit is required without the use of a key. It should not be used when where windows or letter flaps are not in close proximity to the lock to prevent entry by simply break a window or access via letter box by simply reaching the lock from the outside.
BS10621 - is another standard that is even less popular as BS8621. This standard allows key manipulation only from the outside, if someone breaks in through a window they cannot use the door as a means of escape where you could with BS8621. The standard is relevant to locks that can only be locked by a key from the outside.
