In Switzerland, official radon measurements in schools require either a yearlong passive measurement or a minimum three-month passive measurement during the heating season. For cases where these durations are impractical, such as before renovations, short-term methodologies have been developed to estimate radon levels. Since 2018, the Federal Office of Public Health (FOPH) has proposed a short-term real-time measurement procedure to estimate the probability of exceeding 300 Bq/m3 under pressurized winter-like conditions, using a 168-hour protocol. An alternative methodology, adapted from Norway’s 2015 protocol, considers occupancy periods and uses a 120-hour investigation window. This study aims at implementing and comparing these two approaches in schools in the Canton of Fribourg, where previous dosimetric radon measurements were available. Results reveal that both methodologies yielded comparable outcomes, identifying radon concentrations exceeding reference levels when appropriate. However, the protocol considering occupancy offers a more targeted approach, particularly when high radon levels occur outside of occupation hours. This finding emphasizes the importance of accounting for occupancy when assessing radon risks, as it optimizes remediation efforts and ensures measures are proportional to the actual health risk. Both methodologies have practical applications, but incorporating occupancy schedules can better balance safety, cost, and comfort for building occupants.
