Means for Measuring Radon Gas in the Soil

The present invention concerns a means for measuring radon gas in the soil, said means consisting of a continuous-acting radon meter operating on flow-through principle.

Before building a house on a given site, it is useful to make sure of the radon content in the soil. Considering the radon gas content, protective measures required in building a house are to be observed. Radon gas in the soil is nowadays measured either with alpha film boxes dug into the soil or by tubes inserted in the soil, with the aid of which a gas sample is drawn up to be measured in a laboratory. These operations are either time-consuming or unreliable.

The object of the present invention is to provide a measuring means of novel type, which is both rapid and yields extremely reliable measuring results. The measuring means of the invention is characterized in that said measuring means comprises an enclosed volume, the gas within which is measured with a radon meter. With the aid of the invention, the radon gas quantity in the soil is easy to find out very rapidly and reliably and, accordingly, to accomplish the required measures.

An advantageous embodiment of the invention is characterized in that the enclosed volume consists of a tent-like cupola intended to be transferred on the ground to several points where e.g. a house is going to be built. Therefore, the required radon gas samples can be drawn at several points, and also, if a pit is dug within the enclosed volume, it is easier to draw gas into the volume.

A second embodiment of the invention is characterized in that the radon meter is installed through a wall of the volume so that the underpressure in the volume produced by the meter causes gas flow from the soil, and said gas being recorded by the meter as it passes through the meter. As a result, an even gas flow from the soil into the volume is achieved and further, through the meter out. With the even flow-through very reliable measuring results are achieved.

An embodiment of the invention is furthermore characterized in that the lower margin of the tent-like volume is provided with a collar running therearound which seals the volume against the ground. On top of said collar may be placed weights if seen necessary.

An advantageous embodiment of the invention is furthermore characterized in that on the wall of the volume is placed an underpressure meter. Therefore, it is possible to make sure and monitor that the underpressure remains continuously even within the space.

An embodiment of the invention is characterized in that the volume is provided with a separate suction means with which gas is drawn into the volume, for instance via a tube.

An advantageous embodiment of the invention is characterized in that the enclosed volume is a box in which a soil sample may be placed and in which the flow caused by the radon meter circulates the gas therein through the meter. In an embodiment of this kind, a sample taken from the soil is placed in the enclosed volume in which the radon gas emerging from the sample can be recorded with the radon meter provided within said volume.

An embodiment of the invention is furthermore characterized in that in the lower part of the box is placed a soil sample container, on a shelf plane above which the radon meter is placed. A blower in the radon meter generates a gas flow in the box, whereby the gas emerging from the sample circulates as a uniform gas flow through the meter.

An embodiment of the invention is furthermore characterized in that in the upper part of the box there is a window through which the reading displayed by the radon meter can be read.

The invention is described in the following with the aid of examples, referring to the drawings attached in which

FIG. 1 presents a given area in which measurings are carried out at five different points.

FIG. 2 presents the measuring means of an embodiment in oblique top view.

FIG. 3 shows in cross-section the underpressure meter of FIG. 2.

FIG. 4 shows in cross-section the measuring means of FIG. 2.

FIG. 5 presents the measuring means of another embodiment.

FIG. 6 is a similar showing as FIG. 4 but with the addition of a suction means and tube placed into the ground.

The measuring means for radon gas in the soil consists of a radon meter 1 comprising a blower which causes the flow-through of the gas within the meter. The measuring means comprises an enclosed volume 2, 3, the gas located in which is measured with the radon meter. In FIGS. 1-4, the enclosed volume 2 consists of a tent-like cupola to be moved about on a site, as e.g. in FIG. 1, to several points, on which a house is going to be built. The radon meter 1 is installed through a wall of the volume 2 so that the underpressure caused by the meter in the volume causes a gas flow from the soil in the manner indicated by arrows depicted in FIG. 4. The lower margins of the tent-like volume 2 are provided with a collar 4 running therearound, which seals the volume against the ground. If needed, weights such as stones or gravel may be placed on the collar. On the wall of the volume 2 there is an underpressure meter 5. As underpressure is produced in the volume 2, the thin rubber diaphragm 6 is withdrawn inwards and the underpressure may be read on the measuring stick 7.

In the embodiment as shown in FIG. 5, the enclosed volume is a box 3 in which soil sample 8 may be placed. The flow caused by the radon meter 1 circulates the gas therein through the meter. In the lower part of the box is placed a soil sample container 9, the radon meter 1 being located on a shelf 10 thereabove. In the upper part of the box 3 is placed a window 11 wherethrough the readings displayed by the radon meter may be read.

In the embodiment shown in FIG. 6, there is a suction means mounted in a tube which extends into the soil wherein the gas from the soil is drawn into the volume underneath the tent 2.