Publish Time: 2025-08-18 Origin: Site
The European Standard EN 1303:2015 evaluates and tests lock cylinders for durability, fire resistance, attack resistance, and more. It classifies products via an 8-digit coding system, where each digit represents specific performance characteristics against standardized requirements. This coding system enables users to easily compare the performance of different lock cylinders and select the right product for their security specifications.
Classification
One category is identified:
Grade 1: for use by people with a high incentive to exercise care and with a small chance of misuse.
Digit 2 - Durability
Three grades of durability are identified as follows:
Grade 4: 25 000 test cycles;
Grade 5: 50 000 test cycles;
Grade 6: 100 000 test cycles.
Only one grade of door mass is identified as follows:
Grade 0: no door mass requirement.
Three grades of suitability for use on fire resistant / smoke controlled doors are identified:
Grade 0: not approved for use on fire resistant / smoke control door assemblies;
Grade A: suitable for use on smoke control door assemblies;
Grade B: suitable for use on fire resistant and smoke control doors.
Only one grade of safety is identified:
Grade 0: no safety requirement
Four grades of corrosion resistance and temperature requirement are identified:
Grade 0: no corrosion requirement; no temperature requirement;
Grade A: high corrosion resistance; no temperature requirement;
Grade B: no corrosion requirement; temperature requirement: from – 25 °C to + 65 °C;
Grade C: high corrosion resistance; temperature requirement: from – 25 °C to + 65 °C.
Six grades of key related security are identified:
| Requirement | Grade | |||||
| 1 | 2 | 3 | 4 | 5 | 6 | |
Min. number of effective differs | 100 | 300 | 15000 | 30000 | 30000 | 100000 |
| Min. number of movable detainers | 2 | 3 | 5 | 5 | 6 | 6 |
| Direct coding on key | - | - | No | No | No | No |
Torque resistance of plug/cylinder | 2.5Nm | 5Nm | 15Nm | 15Nm | 15Nm | 15Nm |
Five grades of resistance against drilling and mechanical attack are identified:
Grade 0: no resistance against drilling; no resistance against mechanical attack;
Grade A: 3 / 5 min resistance against drilling; resistance against mechanical attack except plug/cylinder extraction;
Grade B: 5 / 10 min resistance against drilling; resistance against mechanical attack except plug/cylinder extraction;
Grade C: 3 / 5 min resistance against drilling; resistance against mechanical attack;
Grade D: 5 / 10 min resistance against drilling; resistance against mechanical attack.
Classification code： 1 6 0 B 0 C 6 0
Encoding Position | Grade | Performance Interpretation |
| 1 | Grade 1 | For use by people with a high incentive to exercise care and with a small chance of misuse |
| 2 | Grade 6 | 100 000 test cycles |
| 3 | Grade 0 | No door mass requirement |
| 4 | Grade B | Suitable for use on fire resistant and smoke control doors |
| 5 | Grade 0 | No safety requirement |
| 6 | Grade C | High corrosion resistance; temperature requirement: from – 25 °C to + 65 °C |
| 7 | Grade 6 | 10 0000 Min. number of effective differs / 5 Min. number of movable detainers |
| 8 | Grade 0 | No resistance against drilling; no resistance against mechanical attack |
Conclusion
The digit code of EN 1303 is not an abstract symbol – it’s the engineering code of cylinder performance. By decoding the meaning behind each digit:
You can avoid the cost waste caused by "over-specification" (e.g., using Grade D drill resistance in standard offices) and prevent safety-critical under-specification (e.g., not selecting Grade B fire-rated lock cylinders for hospitals).
As an experienced manufacturer and supplier of Euro profile cylinders, DIROCK Door lock cylinders certified to:
EN 1303 (mechanical performance)
EN 1634-1 (fire resistance)
DIN 18252 (Dimension)
We deliver:
Different types and various lengths of euro profile cylinder
Master key systems
Verifiable test reports
Decode your security needs now → Explore our EN 1303 certified euro profile cylinders.