How Big Are Radon Particles?

Although radon starts as a gas, it can eventually decay into radioactive radon particles. So how big are these radon particles? It turns out, the size of radon particles can vary depending on what else is in your air.

Radon Particles: Two Sizes

Size #1: Radon Attached to Aerosol Particles (50-300 nanometers)

After decay, radon particles are so small they easily attach to larger aerosol particles. For example, scientists released radon in test chamber along with incense smoke.

Radon particle size

The incense particles averaged around 0.1 microns (100 nanometers), so the radioactive particles that had radon attached were also around 0.1 microns.

Radon particle size

Then they burned an oil candle, and that created smaller particles. Many of those particles were from 0.06 to 0.10 microns (60-100 nanometers). As a result, the radioactive particles were also smaller.

Radon particle size
Size #2: Unattached Radon Particles (.5-3 nanometers)

Radon particles that do not attach to aerosols are free radon atoms and far smaller, ranging in size from .5-3.0 nanometers.

Radon atom
Radon Atom

Read More: Do HEPA Filters Remove Radon Particles?

Do HEPA Filters Remove Radon Gas?

Radioactive radon particles vary in size depending on whether the particle has attached to an aerosol. Attached radon particles are larger in size ranging from 50-300 nanometers, while unattached radon particles range from .5-3 nanometers.

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