Radon, Continuously Monitored at 1.3 pCi/L

What I measure

Radon, continuously. The maximum reading I have recorded is 1.3 pCi/L.

Why continuous rather than a test kit

Because radon is not a stable number, and a single reading is a single moment.

It varies with barometric pressure, with the season, with whether the heating is running, with how much the house is sealed up. A three-day charcoal kit in a mild week can read low on a house that spikes every January. A continuous monitor gives me the actual distribution rather than one draw from it — which is the difference between knowing my house is fine and having been told it was fine once.

What the number means

The EPA action level is 4.0 pCi/L. The WHO recommends a lower reference at 2.7. At 1.3 I am comfortably under both, which is why there is no mitigation system in this protocol — the correct response to a low reading is to keep watching it, not to install something.

That is worth stating plainly because it cuts against the grain of how this kind of content usually goes. The monitoring is not a preamble to buying a mitigation system. It is what tells me I do not need one.

Why it is on the list at all

Radon is the second leading cause of lung cancer in the US and the leading cause among people who never smoked. It is colorless, odorless, and produces no symptom until the outcome. There is no version of noticing it without measuring it, and that combination — high stakes, zero perceptibility, cheap to measure — is exactly the profile that justifies an instrument.