What is the commonly assumed ER value in assessments?

In radon assessments, the effective reduction (ER) value commonly assumed is 0.5 or 50%. This value represents a typical reduction efficiency that can be anticipated from radon mitigation systems under standard conditions. When a mitigation system is installed, it is generally understood that it will reduce the indoor radon concentration to about half of the original level.

By adopting this 50% reduction assumption during assessments, specialists can estimate the potential effectiveness of mitigation strategies, allowing for informed decision-making and planning. The 0.5 ER value serves as a benchmark for comparing different mitigation techniques and designing systems that achieve the best possible reduction while considering the costs and feasibility involved.

In practice, while actual effectiveness may vary based on specific conditions, utilizing this commonly accepted ER value aids in standardizing evaluations and communicating potential outcomes in radon risk management.