Are Radon Levels Higher In Winter Or Summer?

If you’ve performed a radon test in your home, you may be wondering: does it matter when I test? Are radon levels higher in winter or summer? If you conducted a short-term radon test in the spring or summer and your home passed, you may want to think about conducting another test this winter. Radon levels can vary by season, with the highest levels typically occurring during the months that we heat our homes. That means that even if your home’s radon was below the EPA’s suggested action level of 4.0 picocuries per liter of air during the warmer months, it could be above that level during the winter.

Radon Levels Are Higher In The Winter

Solving the gas radon

There are a few different answers to what can affect a radon test in the winter:

The Stack/Chimney Effect

You probably remember learning that warm air rises because it becomes less dense as it heats up. When you heat your home in the winter, the hot air escapes through the top of the house, and more air must be pulled in to equalize the pressure. The air can come from the soil below your house, potentially rising through the foundation, plumbing pipes, or the sump pump pit. Unfortunately, radon gas can come with that air.

A Snowy Barrier

Residents of Colorado Springs and the rest of Colorado are pros when it comes to navigating snowy winter weather. However, even if the snow doesn’t interfere with your daily activities, it may affect the level of radon in your home. When there’s snow on the ground surrounding your house, it can create a layer of water or ice next to the soil that creates a barrier and traps radon underneath. Since the radon can’t escape through the soil outside of the house, it’s more likely to be pulled into the soil under your house and through your foundation.

A Sealed Home

Many of us are used to opening our windows on summer nights to help our houses cool down. By leaving your windows open, you can help dilute the radon gas in your home. Conversely, when you keep your windows sealed during the winter, the radon gas in your home can become more concentrated.

Other Factors

Seasonal variation isn’t the most influential factor when it comes to changes in radon levels.  Radon comes from the decay of radium in the soil, so a change could be caused by an increase or decrease in the amount of radium that has become ripe to decay into radon.  Radon also enters a home by riding on the soil gas that pushes through a concrete foundation, and at various times, the pressure of this soil gas can be lower or greater, greatly affecting radon levels in the building.

Are Radon Levels Always Highest In The Winter?

For most of the 20th century, many homes saw their highest radon levels during the winter. And so far, it seems like all the evidence points to radon gas levels being higher during the winter months.

However, this may not be entirely true.

Data is starting to show that radon is an equal risk across all four seasons. In the 21st century, radon levels in North America are thought to be increasingly even across the seasons. About 25% of homes even have their highest levels of radon during the summer months.

The reasons for this are still being studied. One hypothesis argues that the increased use of air conditioning decreases ventilation of properties in the warmer summer months. A study of Canadian homes paired with winter and summer radon tests showed that 47.5% of buildings showed a minimal difference. 24.7% displaying greater radon in winter, and 27.8% displaying greater radon in summer.

Reduce Radon All Year With A Radon Mitigation System

It can be frustrating to find out your home has high radon levels, no matter what time of year it is. Fortunately, there is something you can do about your elevated levels.

The first thing you can do is test your home. If it tests high, you need to have a radon mitigation system installed right away. And you should test your home during the winter and summer and always opt for a long-term test over a short-term test. If one test shows low, it may be elevated during the other months.

Although there is no “safe level” of radon, the action level for radon levels is 4 picocuries per liter(pCi/L). If your home’s level of radon is above this, contact Pine Breeze Radon Mitigation today. The experts at Pine Breeze Radon Mitigation can install radon mitigation systems to reduce your radon exposure all year long.