With the aim of maintaining the safety of the citizens, a new mandatory protection measure has been included in the Technical Building Code (TBC), by means of which the community is protected from exposure to radon gas inside living premises.

What is radon gas.

Radon gas is a natural gas that has no smell, colour or taste and tends to concentrate in the interior of buildings. It seeps into houses through cracks in the floor or at the junction of the floor and walls, spaces around pipes or cables, small pores in walls made of concrete blocks, holes, drains, etc.

It has been demonstrated that prolonged exposure to radon gas is the second cause of lung cancer, after tobacco. Therefore, many countries, just like Spain, have now included in their Technical Building Codes the obligation to establish health protection measures for people, including radon gas exposure studies and preventive measures in construction.

Therefore, from 2020, the TBC has established for all new constructions, extensions, changes of use and renovations the obligation to limit the concentration of radon gas in interior spaces that are habitable in those buildings located in areas with a foreseeable risk of exposure.

Municipalities with where radon gas is found.

The Ministry of Development has catalogued the municipalities where radon gas may be present in two zones. Zone I is of low activity and zone II is where the presence of radon gas is stronger and more specific prevention measures must be taken.

On this map, we can see which points of the Spanish territory are most exposed to radon gas.

The reference level for radon gas coming from the ground that can’t be exceeded inside the buildings will be 300 Bqm-3, this figure being the average annual radon gas concentration.

In the Balearic Islands, which is the place where Icazar is most active, there is no municipality within zone II, which is defined as having the highest risk of exposure, with the strictest prevention measures to be applied.

The following municipalities in the Balearic Islands are affected by radon gas:

Balearic Islands / Illes Balears

  • Alaró
  • Artà
  • Bunyola
  • Capdepera
  • Deià
  • Es Migjorn Gran
  • Esporles
  • Felanitx
  • Ferreries
  • Fornalutx
  • Lloret de Vistalegre
  • Lloseta
  • Manacor
  • Montuïri
  • Sant Antoni de Portmany
  • Sant Joan
  • Sant Joan de Labritja
  • Sant Llorenç des Cardassar
  • Santa Eulària des Riu
  • Selva
  • Ses Salines
  • Sineu
  • Sóller
  • Son Servera
  • Valldemossa

In the municipalities of the zone I, which is highly present in the Balearic Islands, there will be a protective barrier installed to limit the current of gases from the ground.
The protective barrier may be an anti-radon lath or some other type of barrier that proves to be effective.

Lath-type barriers with a diffusion coefficient against radon gas of less than 10-11 m2/s and a minimum thickness of 2mm will be valid.

The protection barrier will also have the following characteristics:

  1. It shall be hermetically attached to the welded joints and seams,
  2. The joints are welded except the parts designed for elements like cable ducts or similar. Communication gateways that interrupt the continuity of the barrier must limit the passage of air and be equipped with an automatic closing mechanism.
  3. No fissures or cracks must be present that would allow convection currents of radon gas from the ground.
  4. The durability must correspond to the lifespan of the building.

Should you need more information about the measures to be applied, please find the regulations established by the Technical Building Code at the following link:

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