Ironmongery products tested to British and European standards are classified accordingly to show its compliance. Almost all European architectural hardware standards follow a common format of classification under several performance headings. All products are marked with a six or more digit classification coding such as 16-0-C41. Each of these digits represent the levels of product performance for the item as follows:

  • Digit 1 Category of Use: Where and how the cylinder can be used.
  • Digit 2 Durability: The cylinders ability to withstand wear.
  • Digit 3 Door Mass: Requirements relating to door mass.
  • Digit 4 Fire Resistance: Suitability in relation to fire standards.
  • Digit 5 Safety: Requirements for safety in use.
  • Digit 6 Corrosion Resistance: Grading relating to corrosion and temperature.
  • Digit 7 Key Security: Tests relating to security.
  • Digit 8 Attack resistance: Classifying resistance levels to range of attacks.

Cylinders for Locks

BS EN 1303:2015

At William Channon we provide a range of high quality door lock cylinders from approved global manufacturers, all of which conform to BS EN 1303:2015. Designed to ensure a cylinder is fit for purpose this standard covers many different tests for a cylinder to use with a lock. Assessing durability, corrosion, safety, security and resistance to attack, this standard will help you determine the most suitable product for you. If you would like to discuss any of these standards or require advice, please get in touch.

Digit 1 – Category of use

Grade 1: Keys shall resist a torque of 2.5Nm and still be usable.

Digit 2 – Durability

Three grades of durability classify cylinders as either grade 4, 5, or 6 based on the number of test cycles achieved.

  • Grade 4: 25,000 test cycles.
  • Grade 5: 50,000 test cycles.
  • Grade 6: 100,000 test cycles.

Digit 3 – Door mass

As a Grade 0 there is no set requirement for this cylinder.

Digit 4 – Fire resistance

Cylinders are classified as either grade 0, A or B.

  • Grade 0: Not approved for use on fire/smoke door assemblies.
  • Grade A: Cylinders shall be subjected to a smoke test in accordance with EN 1634-3 or materials for the parts of the cylinder responsible for preventing any leakage of smoke shall have a melting point not less than 840 °C.
  • Grade B: Cylinders shall be fire tested in accordance with current fire test requirements of EN 1634-1 or EN 1634-2 or materials for the parts of the cylinder responsible for preventing the spread of fire shall have a melting point not less than 300 °C.

Digit 5 – Safety

Grade 0 – No requirement.

Digit 6 – Corrosion and temperature resistance

Cylinders are classified as either grade 0, A, B or C:

  • Grade 0: No corrosion or temperature requirement.
  • Grade A: high corrosion resistance, no temperature requirement.
  • Grade B: No corrosion requirement, temperature requirement from to – 25 oC and + 65 oC.
  • Grade C: high corrosion resistance, temperature requirement from to – 25 oC and + 65 oC.

Please note that no distinction is made between the inside and the outside of either the cylinder and/or the door. On completion of the test, the cylinder must operate using a maximum 1.5 Nm torque on the key at both – 25 oC and + 65 oC.

Digit 7 – Key Security

Cylinders are classified in grades 1 to 6, where 6 is the highest. The grade of security can differ from one side of a double cylinder to the other. The table below provides a summary of the main security requirements.

Requirement Grade 1 Grade 2 Grade 3 Grade 4 Grade 5 Grade 6
Min number of effective differs 100 300 15,000 30,000 30,000 100,000
Min number of movable detainers 2 3 5 5 6 6
Max number of identical 100% 70% 60% 60% 60% 50%
Max number of identical adjacent steps 2 2 2 2 2
Direct coding on key No No No No
Operation of security mechanism (interpassing) torque 1.5Nm 1.5Nm 1.5Nm 1.5Nm 1.5Nm 1.5Nm
Torque resistance of plug/cylinder 2.5Nm 5Nm 15Nm 15Nm 15Nm 15Nm


Digit 8 – Attack resistance

The table below summarises the main requirements in relation to attack.

Requirement Grade 0 Grade A Grade B Grade C Grade D
Resistance to drilling (net drilling time minutes) 3-5 5-10 3-5 5-10
Resistance to chisel attack (number of defined blows) 30 40 30 40
Resistance to twisting attack (number of defined twists) 20 30 20 30
Resistance to plug/cylinder extraction (Kn minutes) 10




Torque resistance of plug/cylinder 20Nm 30Nm 20Nm 30Nm


Product Marking

This standard requires that the classification relevant to the cylinder shall be quoted in the accompanying documentation, on its labelling or packaging and/or by marking the product itself or by more than one of these methods. The marking/labelling shall include the following:

  • Manufacturer’s name or trademark, or other means of identification.
  • Product model identification
  • The seven digit classification.
  • The number of the European standard (BS EN 1303:2015)

CE Marking

BS EN 1303 has not been designated as a harmonised product standard under the Construction Product Directive and therefore CE/UKCA/UKNI marking of cylinders to this standard is NOT permitted.

Conformity Phrases and Wording

When assessing the correct product for you, it is important to ensure it conforms to the correct standard. Phrases such as “tested to”, “designed to conform to” or “approved to” are not a guarantee that the product is of the appropriate standard. Instead look for products which have been “successfully type-tested for conformity” and that the test reports and/or certificates are available if requested.

Our Products

We stock a range of cylinder systems from global manufacturers such as ABLOY, ASSA and DORMAKABA.


ABLOY locks and cylinders are chosen worldwide for highly sensitive applications. One such product is the PROTEC 2 which provides:

  • A locking system with the ability for different products to be keyed into the same master key system, so all products can be operated with just a single key. This simplifies your locking system and key management.
  • Durable and long lasting thanks to its superior design and precision manufacturing. The unique and patented rotating disc technology provides smooth and reliable functionality also in extreme environments.
  • Option to integrate with electromechanical CLIQ-technology. This electromechanical system is intelligent and highly customizable. It enables flexible and secure access management, including time functions, into your daily operations. And in case of a lost or stolen key it can easily be electronically removed. Both the cylinders and keys collect audit trail of use.


We stock the complete range of ASSA cylinder systems, one of their latest products is the Triton 3900 which offers:

  • Long life patent protection until 2036 giving you peace of mind over your key control.
  • Cylinders exceed the requirements of BS EN 1303:2015 for your assurance of physical security.
  • Quality and durability unmatched: Cylinders and keys are precision engineered and rigorously tested, to ensure the highest levels of quality and durability.
  • Unrivalled master keying capability: This allows the requirements of the largest and most complex suites to be met.


Designed using the latest technology we stock the PEXTRA+, more than just locking doors these cylinders are available with some 20 additional special functions which provide additional security and convenience for a wide range of applications. These functions include:

  • All cylinder types can be integrated into master key systems.
  • Profile families for flexible master key system capacity.
  • Burglary protection is significantly increased through the use of hardened elements and drilling protection pins.

To find out more about these products or alternatives please contact us, our expert team can help you quickly find the right solution for your needs.