New General Regulation on Electrical Installations has been published

The GREI has been restructured and will enter into force on June 1st, 2020.

The current General Regulation on Electrical Installations dates from 1981. Over the years, many adjustments, additions and clarifications have been issued. The FPS Economy has now thoroughly tackled the GREI and given it a completely new structure in 3 Books.

Why a new GREI?

The new GREI aims to:

  • have a better alignment with European standards such as HD 60364, the international standard on electrical installations in buildings.
  • To be better attuned to real conditions.
  • To be clearer and therefore more user-friendly.
  • To be able to incorporate new technologies more easily thanks to the risk analysis
The clarifications and additions that have been published separately over the years have now been incorporated into the text of the GREI, making the whole much more coherent. Contradictions with other regulations, ambiguities and errors have also been eliminated as far as possible. This is not in itself a question of new rules, but of 'recasting' the existing rules. This is not iso much  a question of new rules, but of 'recasting' the existing rules.


What are the major changes?

Treats all types of installations together

Split in 3 separate "Books":

  • Book 1: Low voltage and very low voltage electrical installations
  • Book 2: High-voltage electrical installations
  • Book 3: installations for the transmission and distribution of electrical energy
Subdivision in Articles Book / Chapter / Section / Subsection
Definitions scattered around General terms are grouped together, terms specifically applicable to part of the Book are included in that part. Definitions have also been clarified.

Consult Annex 4 to the Royal Decree which is the Conversion table that links the articles in the old GREI to the sections in the new GREI. The first section of the Annex starts with the new GREI, the second part of the Annex starts with the articles of the old GREI and gives the new subsections.

What are the concrete changes relating to cables?

Installed separately or in a bundle?

  • In the old GREI there was no definition. One relied on a rule of good craftsmanship: if you leave at least 2x the diameter of the thickest cable between each cable, this is not considered a bundle.
  • The new GREI clarifies this: the distance between 2 cables must be greater than or equal to 20 mm in order to be considered as "installed separately".

Fire protection measures

  • The famous Article 104 of the old GREI is succeeded by Section 4.3.3 in the Books of the new GREI. This Section 4.3.3. must be read in conjunction with Section 5.2.7. "Selection and use to limit the spread of fire".
  • The AREI is brought into line with the Construction Products Regulation (CPR): cables intended for fixed installation in buildings or civil engineering works must have a fire reaction according to the CPR. The old F1-F2 and SA-SD characteristics can only be used for cables that are explicitly mentioned in the exceptions. This puts an end to the unlimited use in time of the pre-CPR cables allowed by Note 74.
  • Halogen-free "s1, a1" or "SA+SD" is no longer only according to the risk analysis but is always mandatory in evacuation routes in buildings, in premises accessible to the public (min. 50 people) and in tunnels. This is a clarification compared to the old GREI.
  • The fire resistance of cables remains expressed in terms of FR1 or FR2.
  • From now on, the vital installations will be divided into chapter 5.5. Safety installations (installations that have to remain in service for a certain period of time for the safety of people) and chapter 5.6. Critical installations (for which the maintenance of function is required for reasons other than the safety of persons, e.g. server rooms or livestock farms, etc.).
  • The GREI no longer prescribes a duration of functional maintenance for cables, but refers to "other frames of reference" for this purpose. Think of the Basic Standards, the Hospital Act, ...

When does this new GREI come into force?

The new GREI will enter into force on the first day of the 8th month following the publication of the Royal Decree in the Belgian Official Gazette, i.e. on 1 June 2020.

  • For existing installations or installations already under construction, special regulations are mentioned in Chapter 8.
  • For low-voltage installations whose implementation, modification or extension starts after 1 June 2020, the new GREI is applicable.


The Royal Decree, the 3 Books and the conversion table have been published in Dutch and French only and can be download via the related documents.

Nieuw AREI_Nouvel RGIE