Guide to CPR and Euroclasses Regulations for Cables

If you have ever inspected the sheath of a professional electrical cable, you will have noticed an alphanumeric code printed on it, such as Cca-s1b,d1,a1. Far from being a mere serial number, this nomenclature is vital for the safety of any building.

We are talking about the CPR (Construction Products Regulation). In this technical article, from TiendaCables, we explain in detail what the CPR is, what factors it evaluates regarding fire, and how to correctly read the Euroclasses to comply with the Low Voltage Electrotechnical Regulation (REBT) in Spain.

What is CPR for cables and why is it mandatory?

The CPR (EU Regulation 305/2011) is a mandatory European regulation since July 2017. Its main objective is not to evaluate the electrical conductivity of the cable, but to evaluate the cable's behavior against fire and increase safety in installations.

Any cable designed to be permanently incorporated into construction works (buildings, homes, hospitals, tunnels or infrastructure) must be certified under this directive. In case of fire, the spread of flames and the toxicity of gases emitted by cable plastics can be lethal. The CPR standardizes these risks throughout the European area.

What does the CPR Regulation take into account? The 3 critical factors

To classify a cable, laboratories do not just look at whether it burns or not. The regulation carries out rigorous tests that measure three fundamental parameters during combustion:

1. Flame spread and heat release: Measures how quickly flames travel along the electrical wiring and how much heat they contribute to the fire.

2. Smoke emission (Opacity): Dense smoke impedes visibility, blocking evacuation routes and hindering the work of firefighters.

3. Droplet release: Analyzes whether molten cable releases incandescent droplets or particles, which could start new fires on lower floors.

4. Acidity and toxicity (Additional): Measures the corrosiveness of emitted gases (the dreaded halogens), which can cause severe respiratory damage and destroy nearby electronic equipment.

The CPR Euroclasses: From A to F

The CPR classifies cables into 7 main groups or Euroclasses, ordered from highest to lowest fire resistance (the "ca" ending means cable):

• Aca (No reaction): Incombustible cables. They usually use mineral insulation.

• B1ca and B2ca (Minimal/very low reaction): Cables with exceptional fire performance. They do not propagate flames and their heat release is almost nil.

• Cca (Low reaction): These are known as high-safety (AS) cables or halogen-free cables. They are mandatory in Spain for Public Access Premises.

• Dca (Moderate reaction): Improved safety cables. They have fire performance, but inferior to Cca.

• Eca (Basic reaction): They pass the basic flame non-propagation test, but smoke or acidity performance is not guaranteed. These are typical standard PVC cables for interior housing.

• Fca (Undetermined): They do not have fire resistance properties. They are not suitable for fixed installation in buildings.

How to read a cable's full code? (Additional Criteria)

For Euroclasses from B1ca to Dca, the regulation requires a technical breakdown detailing smoke (s), droplet (d), and acidity (a) behavior.

Let's take as an example the standard required by the REBT for hospitals, offices, or cinemas in Spain: Cca - s1b, d1, a1.

• "s" criterion (Smoke):

  • s1: Low smoke production and slow smoke spread. (Divided into s1a and s1b according to light transmittance).

  • s2: Intermediate smoke values.

  • s3: No declared smoke performance.

• "d" criterion (Droplets):

  • d0: No falling of flaming droplets or particles.

  • d1: Falling of flaming droplets that extinguish in less than 10 seconds.

  • d2: No performance (particles fall continuously burning).

• "a" criterion (Acidity):

  • a1: Very low electrical conductivity and gas acidity (low toxicity).

  • a2: Intermediate values.

  • a3: No declared performance.

CPR is not a detail, it is the basis of a safe installation

Installing an Eca cable (standard PVC) in an office suspended ceiling or an evacuation route is a technical and legal negligence. In the event of an inspection by the Industry or, worse, an accident, the installer assumes full criminal responsibility if the material does not have the CPR certification required for that environment.

Making the right choice starts with being informed. At TiendaCables, we specialize in professional electrical materials. In our technical catalog, you will find all halogen-free (Cca) wiring and electrical cables certified under the strictest European Union standards, with their respective Declarations of Performance (DoP) available.

Don't risk it with generic materials. Visit our CPR cabling section and secure your next project today.