Radon levels: What do they mean?

Airthings most frequently asked question? "What do my radon levels mean?" Below we explain everything you need to know about your levels. Arm yourself with the information you need to make small changes to your home, improve your radon levels, and your health!

What is radon gas, and how is it measured?

Radon, an invisible, odorless, and potentially harmful radioactive gas, is a significant concern for homeowners due to its scientific link to lung cancer. 

Radon exposure is typically quantified in becquerels per cubic meter (Bq/m³). However, in the United States, the commonly used unit of measurement is picocuries per liter (pCi/L). It is essential to acknowledge that radon gas exposure can differ from one geographical region to another, and it is crucial to adhere to local recommendations, often provided by authoritative bodies like the World Health Organization (WHO) and EPA (United States Environmental Protection Agency).

Radon gas is generated by the radioactive decay of radium, an element that was originally discovered in 1898 by Pierre Curie, Marie Skłodowska Curie, and G. Bemont. Radioactive elements are unstable, always in a constant struggle to decide whether to hold onto all of their atomic energy in the nucleus or release some of it. That "decay" of the nucleus releases radiation.

One curie is equal to the radioactivity of one gram of radium, which decays at 2.2 trillion disintegrations per minute3. Sounds fast, doesn't it? It also sounds small, right? Read on.

Why it is important to control healthy indoor radon levels?

Measuring radon exposure at home or building is key to protecting the health of anyone breathing the air, but interpreting those levels is not quite as exact without radon tests and monitoring. As they say, everything is relative, and what is an acceptable radon gas level to one country or organization may differ from what is acceptable to another. This is influenced by numerous factors including the type of rocks and soil beneath a building, ventilation, and duration of time spent in the building.

One thing remains certain: radon exposure can cause lung cancer. According to EPA estimates approximately 21,000 people die from radon-related lung cancer every year in the United States and 20,000 in the EU.

That alone should be the reason to find out if you, or your family, are being exposed to excessive levels of the dangerous gas. Radon gas levels in the home need to be monitored daily as the levels fluctuate over time to reduce health risks. Radon can build up in the air in any home or building whether it has a basement, is sealed or drafty, or is new or old. There is no known safe level of radon and you should always aim to have the lowest level.

The World Health Organization (WHO) recommends that countries adopt reference levels for safe levels of the gas of 100 Bq/m3 (Becquerel per cubic meter). If this level cannot be implemented under the prevailing country-specific conditions, WHO recommends that the reference level should not exceed 300 Bq/m3.

How to read radon level chart?

Airthings View Plus, View Radon, Wave Radon, and Wave Plus have color-coded visual indicators. This makes it easy to get an overview of the air in your home. In addition, you can check in the Airthings app if the radon sensor is good (green), fair (amber), or poor (red).

Radon levels chart from Airthings

What is the difference between pCi/L and Bq/m3?

Picocuries per litre of air, or pCi/L: is one of the preferred measurements for the speed of decay in radon, is equal to one trillionth of a curie, abbreviated as pCi. The pCi unit is used in the United States because it is required by federal law. Just about everywhere else that uses the metric system, including the WHO, measures in Becquerels. 1 pCi/L is equal to 37 Bq/m3.

The Becquerel unit, abbreviated Bq/m3: is named after the scientist Henri Becquerel. The preferred radon level measurement unit is Becquerels per cubic meter, Bq/m3. One Becquerel equals one radioactive disintegration per second.

How to Interpret results of the radon test

To grasp the significance of radon gas levels, let's dissect the interpretations of radon readings:

1. Minimal Levels (Up to 1.3 pCi/L or 50 Bq/m3): concentrations below 1.3 pCi/L are considered safe radon levels, necessitating no immediate action. Nonetheless, continuous monitoring is prudent.

2. Low Levels (1.3 to 2.6 pCi/L or 50  to 100 Bq/m3): levels falling within this range are classified as acceptable radon levels. While immediate intervention is not imperative, regular monitoring is advisable. Additionally, homeowners can experiment with ventilation and sealing foundation cracks as a preventive measure.

3. Moderately High Levels (2.7 to 4 pCi/L, or 100-150 Bq/m3): levels between 2.7 and 4 pCi/L are considered moderately high, warranting attention. Initial steps may involve enhancing ventilation and monitoring the situation. If no improvement is observed after three months, it is advisable to consult a professional radon mitigator.

4. Risk Levels (Above 4 pCi/L or 150 Bq/m3 and up): levels exceeding 4 pCi/L (150 Bq/m3) are deemed high, demanding immediate action. In such cases, homeowners should promptly seek for professional radon mitigation to address the radon problem.