SS 312 Specification For Cylinders For Locks – Update 2017

Master Locksmiths Association

First a bit of background to SS312 – the original and still highest standard for lock cylinders available.

A meeting was held by Secure by Design in 2010 which highlighted the need to combat the growing number of cylinder attacks that included snapping. Sold Secure was first off the mark with the publication of SS 312 Diamond in late 2010. This specification was the first attack test for cylinders to incorporate a specific test for the vulnerability to snapping, with other similar standards being developed and published over a year later. SS 312 used BS 3621 tools as a base for attack testing and then added heavier tools including vice grips and cylinder snappers as well as the existing manipulation tools and drills used in GVA. This means that unlike other standards a cylinder can be snapped and then drilled!

Problems highlighted by ACPO (Association of Chief Police Officers) saw some fairly major changes made to PAS 24 and BS 3621 GVA testing. Several meetings took place at the end of 2010 for all stakeholders to have a say as to what the changes should be to amend this specific problem and whilst other standards try to solve the problem by introducing a cylinder and handle combined test, for example TS007 introduces a star rating system where a minimum 3 stars is required allowing this to be achieved via a 1 star approved cylinder used in conjunction with a 2 star rated handle, or for a cylinder only option then to the need for a 3 star rated cylinder, the Sold Secure 312 test manages to qualify (and outperform) the 3 star requirement of TS 007 by being a cylinder only solution.  (There are other Sold Secure standards that can be used to approve door furniture such as handles and escutcheons.)

The diamond level of the SS312 Standard includes EN 1303 testing by a UKAS accredited test house, BS 3621 GVA testing by expert MLA testers and a two-minute attack test on the cylinder itself. The main thrust of this is to test the cylinder’s vulnerability to snapping/pulling in particular. Whilst a two-minute attack test does not sound like a very harsh test, the cylinder is exposed in the test block (as if the handle has been removed) with a 45mm hole around the cylinder (simulating an attack on the doors structure to provide room for attacking the cylinder). Tools such as vice grips and cylinder snappers have been included in the tool list for this particular test to fully replicate the types of attack that are being increasingly reported. To date, several manufacturers have been successful in gaining SS 312 Diamond and Sold Secure is working with others as they develop improvements to their products. This specification offered the very first third party tested genuine security cylinder that will be recognised as having genuine attack resistance on cylinder only and immediately raised interest by ACPO Secured by Design who have confirmed they will accept SS312 Gold as an equivalent to a 1* Kitemarked Cylinder and SS312 Diamond as an equivalent to a 3* Kitemarked Cylinder for their certification requirements.

Several subtle changes have been made to SS 312 Diamond over the years as our knowledge grows of vulnerability such as making the attack test longer and making clear to manufacturers that a tester is allowed to damage test blocks during attacks (as a real burglar would). The next expected change will be to introduce an additional test key requirement into the BS 3621 GVA test quoted directly in SS 312 within the next 12 months, thereby making the bumping test more representative of real world scenarios.

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