Best location for monitoring?

I am curious what people on this forum think is the best location for mounting a radiation monitor for sampling outside air from INSIDE a house (if that's even possible). I've heard some mount their units by a window (or on a window with the monitor pointing outside through the window). Does this really make a difference? Are there better locations or methods to sample outside radiation from inside a house?

Hi there, I do this now with a unit mounted outside on a post, set a cables running into the shack inside. Also have similar unit mounted externally (the tube itself) on the outside of my truck with the unit mounted inside the cab. Is this what your talking about?

I actually was wondering how effective mounting units INSIDE a house are at measuring outside radiation levels, and where the sensor placement should be to obtain the most accurate results. Some people tape their sensors to windows, but does that really help? I don't want to expose my sensor to the elements outside. But I would like to be able to obtain readings that are characteristic of radiation levels that are outside. Window mounting seems logical, but do these charged particles get absorbed by glass more than wood or insulation, or stucco?

There's no question that outside units are the fastest detectors of incoming wind-borne radiation. Inside detectors, though will always react to sustained outside higher levels; it's just delayed due to the slow but guaranteed air leakage. Inside detectors can be affected by geography, as some areas have more ground Radon leaking through basement walls and that could affect inside detectors. Also, high altitude places have more gamma from cosmic sources, so are affected by heavy ceilings. (I haven't seen any real studies on this yet; just observations from various sites).

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:

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.

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.

Hey, this is going way off topic. Outdoor detector: fast detections but be prepared for more alarms.

Hey, I don't mind the extra detail AT ALL!! It's all good and useful information. Thanks for taking the time.

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.

Bert490 wrote:

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.

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.