What are non destructive testing?

Non-Destructive Testing – CND (or Non Destructive Testing – NDT) are non-invasive experimental techniques used to assess the integrity of the material under examination without altering or destroying its state.

One of the most widely used techniques in CND’s work is radiography:

By using an X-ray tube and a detection system consisting of a photographic plate with a high blackening density, it is possible to check, for example, internal defects in semi-finished products or defects in welds. Usually the working voltages range between 100 and 500 kV with currents typically not exceeding 12 mA.

As required by current regulations in terms of radiation protection, it is necessary to create protective barriers in order to reduce the dose level to the desired values. This helps to limit the exposure of the public and personnel working outside the room during the use of the radiogenic machine. Of course, the entrance door to the bunker is also part of these barriers.

Bariblock’s proposal

In this specific case, we proposed to the customer an alternative solution to the classic lead door, a solution that was not only cheaper but also eco-sustainable:

A door made of high-density reinforced barytic concrete, ρ = 3,300 kg/m³.

The geometrical characteristics of the door designed and manufactured by us are:


Height [mm] Width [mm] Thickness [mm] Weight[kg]
3.600 3.300 300 13,000 kg


Given the considerable weight, we have installed an electromechanical handling system integrated with a manual handling system in the event of a power failure.

To ensure the correct shielding of the bunker, an excavation approximately 400 [mm] deep, with respect to the floor level, was carried out, which allows the door to slide on a rail ensuring the overlap of the door with respect to the floor.