How CPR Testing Ensures Cable Safety: EN 50399, EN 61034, EN 60754

■ Introduction: The Role of CPR Testing in Cable Safety

In modern buildings, safety is not only about the external structure, but whatever rests within the walls too. If a fire happens, electrical and telecommunication cables can fuel it, generate toxic smoke, or give off corrosive gases all of which may hurt people and machines.

To address these risks, the EU’s Construction Products Regulation (CPR) establishes unified fire performance standards for cables used in permanent installations. The testing process—based on standards like EN 50399, EN 61034, and EN 60754—ensures that every certified cable meets strict requirements for flame spread, smoke production, and acidity.

■ Main Testing Standards Explained

EN 50399 – Fire Propagation and Heat Release

EN 50399 is the cornerstone of CPR testing. It evaluates how a cable behaves under real fire conditions using a vertical flame spread test inside a controlled chamber.

Key parameters measured:

• Flame spread height over time

• Heat release rate (HRR)

• Total heat released (THR)

• Smoke production rate (SPR)

• Optical density (smoke visibility)

Purpose:
To classify the cable into Euroclasses (B2ca, Cca, Dca, Eca) based on its ability to resist flame propagation and limit heat energy. For instance, a B2ca cable demonstrates minimal flame spread and very low heat release — ideal for hospitals or transport hubs.

EN 61034 – Smoke Density Measurement

Burning resistance might not prevent the formation of smoke, which still presents an impediment to evacuation and asphyxiation.

To quantify the smoke density, EN 61034 uses the assessment of light transmittance through smoke, formed during controlled combustion.

Test conditions:

• Cable samples burned inside a 3 m³ chamber.

• A photometric system measures the percentage of light passing through smoke.

Result interpretation:

• High transmittance (>60%) = Low smoke density (s1 classification)

• Low transmittance (<20%) = High smoke density (s3 classification)

This test defines the “s” parameter in Euroclass ratings (e.g., Cca s1 d0 a1).

EN 60754 – Acidity and Corrosivity of Gases

As halogenated materials are combusted, hydrochloric and hydrobromic acids get liberated, which in turn corrode metals and cause failures in electronic systems.

EN 60754 consists of two parts:

• EN 60754-1: Measures halogen acid gas emission.

• EN 60754-2: Measures acidity and conductivity of combustion gases.

Pass criteria:

• pH > 4.3

• Conductivity < 10 μS/mm

Low acidity corresponds to the “a” parameter in CPR classification (a1 = low acid emission).

■ Testing Conditions and Measurement Environment

CPR testing requires highly controlled laboratory setups:

• Temperature-controlled flame chamber simulating cable bundles mounted vertically on ladders.

• Airflow monitoring for consistent combustion.

• Calorimeter sensors tracking oxygen consumption (for heat release rate).

• Optical instruments measuring smoke transmittance.

• Gas collection apparatus for acidity and halogen detection.

Sample requirements:

• Standardized cable lengths (3.5–4.5 meters)

• Identical bundle arrangement

• Repetition to verify consistency

■ Third-Party Notified Bodies and Factory Production Control (AVCP)

Per the CPR structure, all assessments are required to be performed by EU-recognized Notified Bodies such as TÜV, VDE, or Intertek.

Key responsibilities:

• Carry out EN 50399, EN 61034, EN 60754 testing by ourselves.

• Create Declaration of Performance (DoP) and CE certificate.

• Inspect the AVCP process constantly through periodic audits, to verify that factory production remains consistent with the samples previously tested.

■ Zion Communication’s Internal Testing and EU Certification Process

Zion Communication follows a dual-layer testing strategy combining in-house quality control and third-party certification.

Internal quality steps:

• Routine smoke density checks (EN 61034 equivalent) in small-scale chambers.

• Acidity simulation tests verifying halogen-free LSZH compounds.

• Flame propagation verification on finished cable assemblies.

External certification:

• Samples submitted to EU Notified Labs for EN 50399/60754/61034 tests.

• Certification under AVCP System 1+, meaning continuous auditing of factory production by authorized inspectors.

• Each product range (e.g., fire alarm, power, or data cable) receives its Euroclass rating (Cca s1b d0 a1) and corresponding DoP number.

Through this rigorous process, Zion ensures its CPR-compliant cables deliver verified safety performance for European construction projects.

■ Conclusion: Certified Safety, Proven Reliability

CPR testing—anchored by EN 50399, EN 61034, and EN 60754—goes beyond regulatory compliance; it safeguards human life and infrastructure.
By adhering to these standards and maintaining transparent certification procedures, Zion Communication demonstrates a commitment to producing safe, low-smoke, halogen-free cables that meet the highest expectations of the EU market.

Contact us for more information

Luke Han is a Product Manager and Director at Zion Communication, 

Specializing in fire, security, and alarm solutions. With extensive industry experience, 

Dedicated to delivering high-performance, reliable products that are tailored to customer needs.

luke@zion-communication.com

0086 19883212162