Mechanical ventilation as radon reduction strategy: Methodologies for calculating flow rates and field experiences

¹ Freelance engineer – Bolzano (BZ), Italy
² Freelance engineer – Mantova (MN), Italy

Abstract

Radon is a naturally radioactive gas that represents a health risk when it accumulates indoors. Controlled Mechanical Ventilation (VMC) is an effective strategy for mitigating radon concentrations, improving indoor air quality, and reducing occupant exposure. The principle on which it is based is the dilution of pollutants, which may include radon. Numerous scientific articles, regulations, and technical documents address the topic of VMC as a strategy for reducing radon concentrations. This study presents a detailed review to highlight critical issues and strategies in the design and management of VMC systems against radon. In addition to the correct determination of flow rates, an important design aspect is the assessment of their imbalance, aimed at creating slight overpressure in the rooms. This article explores methodologies for calculating the ventilation flow rates required for radon remediation, integrating theoretical models with practical field experience. Case studies that illustrate the practical application of these methodologies in real contexts, highlighting the benefits and challenges encountered during implementation, are described. The results show that proper design and management of VMC can significantly reduce radon levels, helping to create healthier and safer indoor environments.