Best location for monitoring?
An interesting thing is that the US EPA has recently stopped measuring and publishing real-time outdoor Beta air filter measurements (they still do Beta lab analysis though). The reason they give is:
I think that much of the "interference" may have been Radon and its decay products sticking to the filters. It is hard to identify quickly without a scintillation detector (and someone willing to measure quickly), but Radon products decay in hours and are sort of identifiable if the decay is this fast. It's kind of a catch-22 situation, as there is no other way for citizen scientists to quickly detect dangerous plumes, say from an accidental nuclear release. The safest approach is to react to higher outside readings by not exercising outdoors, etc. on such days. But there is a wide range of personal perceptions on risk vs. exposure to surface Radon (basements and mines more widely accepted as riskier). Some say any exposure is bad; others reason we have a natural ability to resist low levels of exposure.
In the past, EPA attempted to supplement this laboratory analysis by adding near real time beta detectors to the RadNet monitors. EPA has discontinued this because the detectors were not able to confirm or rule-out the presence of beta emitters, did not provide identification or quantification of specific nuclides, were subject to various interferences, and did not provide actionable information to EPA scientists.
Hey, this is going way off topic. Outdoor detector: fast detections but be prepared for more alarms.
You seem to imply from your statement that it takes longer for radiation to seep into a house to affect readings inside a house. I was under the impression that the radiation of say a passing cloud of radon, might cause radioactive components to pass through the walls and windows of a house and be detected that way - particularly if a detector is placed right against a window or an outside wall. But perhaps the higher energy particles emitted by the cloud decay too rapidly to travel the distance necessary to successfully penetrate a window or wall?
Sorry for the newb questions. But I've never seen a discussion on this before.
It seems odd to me that the EPA would do this if they have been doing it for years. I also heard that the government was going to stop testing fish stock in the Pacific for radiation, even though the threat from Fukushima is no-where close to being over. If anything, it should be ramped up. But who knows why the powers-that-be do what they do? I'm not entirely certain their reasoning is sound - or trustworthy.