Patent Description:
It is known that radon is a cancer causing radioactive gas. Radon comes from the decay of uranium found in igneous rock, soil and water. It has been documented that exposure to radon gas introduces an increased risk of lung cancer. Unfortunately, radon has no smell or taste. Accordingly, in practice it is impossible to detect the presence of radon without conducting a radon specific test. Since radon has a higher density than air, the presence of radon is in particular a problem in lower levels of building and work environments.

Radon can enter buildings through cracks and other openings in the lowest levels of the building being arranged in contact with or in close proximity to soil, rock or ground water. In some buildings, a ground water collection system is installed to hold rain and standing water. These ground water collection systems collect water from around and under the building foundation using a system that comprises drainage pipes.

It is known to remove radon from building structures by venting with an exhaust fan and hereby actively depressurise the ground areas surrounding the building structure. This approach is, however, not suitable and practical in many situations. When a ventilator is arranged inside the building structure or close thereto, significant noise inside the building is a problem.

Many alternative prior art solutions are, however, expensive and complex and require that substantive constructional amendments are made. Accordingly, the typical prior art solutions cannot be retrofit to existing systems.

Some systems comprise a collecting wellarranged inside the building. <CIT> discloses a method for removing radon in such a system. However, these systems are associated with a leakage risk that potentially can contaminate the building.

<CIT> anticipates the features of preamble of the independent claims, and discloses a HVAC system connected to a vent pipe, wherein soil gas pressure below a building structure is reduced by establishing a suction point in proximity to a penetration of an existing sub-slab refrigerant line chase of the HVAC system and placing the same in communication with the chase. The chase is then sealed except for passage of the refrigerant lines or other internal conduits and an air pump connected to the vent pipe is connected outside the structure at the exit port of the chase to exhaust soil gas, including radon, from the suction point to the outside of the structure through the sealed chase line. This solution is, however, not suitable for draining away water to keep a ground water level lower than the level of the drainage system below the building. Accordingly, it would be desirable to have an alternative solution suitable of draining away water and radon-containing air and removing radon-containing air from the subsoil.

<CIT> discloses a radon collecting system that removes radon-containing air from the soil proximate a basement. This solution is, however, not suitable of at the same time draining away water by using gravity to keep a ground water level lower than the level of the drainage system and removing radon-containing air via drainage pipes. Moreover, the solution requires a visible upright pipe extending from below the floor into the basement and further out through an outer wall. Accordingly, it would be desirable to avoid said upright pipe and have an alternative solution suitable of at the same time draining away water by using gravity to keep a ground water level lower than the level of the drainage system and removing radon-containing air via drainage pipes.

<CIT> discloses a method of retrofitting an underground water drainage sump system below a floor slab for protecting the floor slab. The method comprises the steps of forming a sump hole to extend through a floor slab and into underground below the floor slab; forming a plurality of lateral passageways in the underground below the floor slab so as to extend outwardly from said sump hole along and below the floor slab to the vicinity of an outer perimeter of the floor slab; inserting a plurality of perforated hollow collection pipes into the lateral passageways such that outer ends of said collection pipes extend to the vicinity of the outer perimeter of the floor slab and inner ends of said collection pipes are disposed in flow communication with said sump hole; and placing a sump pump into said sump hole for pumping from said sump hole drainage water discharged into said sump hole from said collection pipes. When using instead of a sump pump a vacuum or exhaust fan, the operation of the vacuum or exhaust fan produces a condition of sub-slab depressurization below the floor slab which causes the removal of the polluting gases through the system, preventing the gases from entering the building.

Accordingly, it would be an advantage to be able to provide an alternative solution.

It is an object of the present invention to provide a system that is suitable for being retrofit to an existing drainage system that comprises a number of drainage pipes arranged under a building providing removal of toxic gases. It is also an object to provide a method, for the same purpose.

The object of the present invention can be achieved by a system as defined in claim <NUM> and by a method as defined in claim <NUM>. Preferred embodiments are defined in the dependent subclaims, explained in the following description and illustrated in the accompanying drawings.

The system according to the invention is a system for removing radon from a drainage system, wherein the system comprises a building and a drainage system that comprises a ventilator, a collecting well and at least one drainage pipe installed under a building, wherein the collecting well is configured for being installed outside the building, wherein the drainage pipes are in fluid communication with the collecting well, wherein the collecting well is arranged outside the building, wherein a ventilator is provided in the collecting well, wherein the ventilator is connected to the drainage pipe that extends into the collecting well, wherein said drainage pipes incline into the collecting well to ensure that:.

Hereby, it is possible to provide a system that is suitable for being retrofit to existing drainage system that comprises a number of drainage pipes arranged under a building.

According to the invention, the term "the ventilator is provided in the collecting well" means that the ventilator is present in the collecting well.

The system is configured to remove radon from a drainage system that comprises a number of drainage pipes arranged under a building, wherein the drainage pipes are in fluid communication with a collecting well.

Some buildings are equipped with a drainage system comprising drainage pipes arranged under a building, wherein the drainage pipes are arranged and configured to guide water into a collecting well that is arranged outside the building.

It is known to install a ventilator outside the collecting well and connect the ventilator to a drainage pipe that extends into the collecting well. Hereby, the ventilator can depressurize the ground areas under the building and remove radon from the ground area under the building.

According to the invention, the ventilator is installed into the collecting well. one embodiment, the ventilator comprises an electrical motor.

It may be an advantage that the ventilator comprises or is controlled by a regulation unit that is configured to regulate the speed of the ventilator. In one embodiment, the ventilator is designed as an exhaust fan.

In one embodiment, the ventilator is connected to a guide pipe that is protruding from the collection well and has a distal portion provided outside the building. Hereby, it is possible to guide away the radon-containing air through the guide pipe so that the air is released in a sufficiently large distance from the building. Moreover, noise generated by the ventilator is reduced.

In one embodiment, the ventilator is connected to a drainage pipe that extends into the collecting well, wherein the ventilator is connected to said drainage pipe by means of a T-branch joint for pipes. Hereby, it is possible to drain water from the drainage pipe into the collecting well by means of the T-branch and at the same time use the T-branch to guide away radon-containing air from at least one drainage pipe.

According to the invention, the drainage pipe extends into the collecting well and said ventilator is placed in said collection well.

In one embodiment, the T-branch is arranged in such a manner that one pipe portion of the T-branch extends downwardly towards a bottom of the collecting well, whereas another pipe portion of the T-branch extends upwardly towards an open end of the collecting well. Hereby, it is possible guide water from the drainage system downwards into the collecting well and guide away radon-containing air from the drainage system via the upwardly extending pipe portion of the T-branch.

In one embodiment, the guide pipe extends through a side wall of the collecting well. Hereby, it is possible to cover the collecting well with a cover without a hole for a through-going pipe.

In one embodiment, the system comprises at least one detection unit arranged and configured to detect the radon concentration in one or more predefined positions, wherein the system comprises a regulation unit configured to regulate the activity of the ventilator on the basis of the detections made by the detection unit. Hereby, it is possible to minimise the energy consumption of the ventilator.

In one embodiment, the system comprises one or more detection units arranged inside the building, wherein the one or more detection units are configured to detect the radon concentration.

In one embodiment, the regulation unit is configured to control the ventilator in such a matter that the ventilator provides an intermittent ventilation.

In one embodiment, the regulation unit is configured to control the ventilator in such a matter that the ventilator provides a continuous ventilation.

In one embodiment, the regulation unit is arranged inside the building. In one embodiment, the building comprises a basement, wherein the regulation unit is arranged inside the basement of the building.

In one embodiment, the distance between the collecting well and the distal portion of the guide pipe is at least <NUM> meter. Hereby, it is possible to guide the radon-containing air away from the collecting well and further away from the building.

In one embodiment, the distance between the collecting well and the distal portion of the guide pipe is at least <NUM> meters.

The method according to the invention is a method for removing radon from an existing drainage system that comprises a ventilator, a collecting well and a number of drainage pipes arranged under a building, wherein the drainage pipes are connected to a collecting well, wherein the method comprises the step of evacuating radon-containing air from the drainage system into the collecting well, wherein the collecting well is arranged outside the building, wherein the ventilator is arranged inside the collecting well and configured to:.

wherein said drainage pipes (<NUM>) incline into the collecting well (<NUM>) to ensure that:.

Hereby, it is possible to provide a method by which it is possible to update a drainage system that comprises at least one drainage pipe arranged under a building.

According to the invention, in order to evacuate the radon-containing gas, the method comprises the step of applying a ventilator arranged in the collecting well,
wherein the ventilator is connected to a drainage pipe that extends into the collecting well, wherein the ventilator is further connected to a guide pipe, which protruding from the collection well and has a distal portion provided outside the building.

Hereby, it is possible to guide away the radon-containing air through the guide pipe so that the air is released in a sufficiently large distance from the building. Other undesirable gasses or particles can be guided away through the guide pipe and released in a sufficiently large distance from the building. Moreover, noise generated by the ventilator is reduced.

In an embodiment, the method comprises the step of retrofitting an existing drainage system that comprises at least one drainage pipe arranged under a building, wherein the drainage pipes are in fluid communication with a collecting well.

Hereby, it is possible to update existing drainage systems so that radon-containing air can be evacuated from the drainage system.

In an embodiment, the method comprises the step of applying a ventilator that is connected to the drainage pipe by means of a T-branch joint for pipes, wherein the drainage pipe extends into the collecting well, wherein the T-branch is arranged in such a manner that one pipe portion of the T-branch extends downwardly towards the bottom of the collecting well, whereas another pipe portion of the T-branch extends upwardly towards the open end of the collecting well. Hereby, it is possible guide water from the drainage downwards into the collecting well and guide away radon-containing air from the drainage system via the upwardly extending pipe portion of the T-branch.

In one embodiment, the method comprises the following steps of:.

Hereby, it is possible to minimise the energy consumption of the ventilator.

In one embodiment, the method comprises the step of detecting the radon concentration in one or more positions inside the building by using one or more detection units arranged inside the building, wherein the one or more detection units are configured to detect the radon concentration.

In one embodiment, the method comprises the following steps of guiding the radon-containing air from the drainage system to the collecting well and further guiding the radon-containing air from the collection well away from the collection well via a guide pipe protruding from the collection well, wherein the distal portion of the guide pipe is provided outside the building. Hereby, it is possible to evacuate the radon-containing air in a larger distance from the building.

In one embodiment, the distance between the collecting well and the distal portion of the guide pipe is at least <NUM> meter.

The invention will become more fully understood from the detailed description given herein below. The accompanying drawings are given by way of illustration only, and thus, they are not limitative of the present invention. In the accompanying drawings:.

Referring now in detail to the drawings for the purpose of illustrating preferred embodiments of the present invention, a system <NUM> of the present invention is illustrated in <FIG>.

<FIG> illustrates a schematic side view of a system <NUM> according to the invention. The system <NUM> is configured to remove radon <NUM> from a drainage system that comprises at least one drainage pipe <NUM> arranged under a building <NUM>. The system <NUM> comprises a collecting well <NUM> arranged outside the building <NUM>.

In one embodiment, the drainage system comprises a plurality of drainage pipes <NUM>, wherein the drainage pipes <NUM> are in fluid communication with the collecting well <NUM>. The collecting well <NUM> comprises an upper open end arranged at ground level. The ground <NUM> is indicated.

A major part of the collecting well <NUM> is arranged below ground level. The top portion of the collecting well <NUM>, however, is arranged at ground level. A drainage pipe <NUM> extends through the wall <NUM> of the collecting well <NUM>. The drainage pipe <NUM> inclines into the collecting well <NUM>. Accordingly, water collected by the drainage system will be guided into the collecting well <NUM> via the drainage pipe <NUM>. It can be seen that water <NUM> and radon <NUM> flow through the drainage pipe <NUM> into the collecting well <NUM>.

The T-branch <NUM> comprises a first pipe portion <NUM> and a second pipe portion <NUM> extending in extension of the first pipe portion <NUM>. The T-branch <NUM> is arranged in such a manner that the first pipe portion <NUM> of the T-branch <NUM> extends downwardly towards the bottom of the collecting well <NUM>, whereas the second pipe portion <NUM> of the T-branch <NUM> extends upwardly towards the open end of the collecting well <NUM>. Accordingly, water <NUM> from the drainage pipes <NUM> is guided via the first pipe portion <NUM> into the bottom of the collecting well <NUM>. Moreover, air containing radon <NUM> is guided via the second pipe portion <NUM> into a pipe section <NUM> that is connected to the T-branch joint <NUM>.

The collecting well <NUM> is arranged outside a building having a basement <NUM>. A ventilator <NUM> is provided in the collecting well <NUM>. The ventilator <NUM> is connected to the drainage pipe <NUM> by means of a T-branch joint <NUM> for pipes. The drainage pipe <NUM> extends into the collecting well <NUM>. The ventilator <NUM> is connected to the pipe section <NUM> that is connected to the T-branch joint <NUM>.

A pipe structure <NUM> is connected to the lower portion of the collecting well <NUM> and protrudes therefrom. It can be seen that the pipe structure <NUM> inclines away from the collecting well <NUM>. Hereby, excess water can be guided away from the collecting well <NUM> via the pipe structure <NUM>.

The system <NUM> comprises a guide pipe <NUM> that extends through a side wall <NUM> of the collecting well <NUM>. The guide pipe <NUM> is configured to guide away radon <NUM> from the collecting well <NUM>. Accordingly, it is possible to guide away the radon-containing air <NUM> through the guide pipe <NUM> so that the radon-containing air <NUM> is released in a sufficiently large distance from the building and that noise (hearable from the building) generated by the ventilator <NUM> can be reduced.

The system <NUM> comprises a detection unit <NUM> arranged and configured to detect the radon concentration in the basement <NUM> of the building <NUM>. The system <NUM> comprises a regulation unit <NUM> configured to regulate the activity of the ventilator <NUM> on the basis of the detections made by the detection unit <NUM>. The detection unit <NUM> is arranged in the basement <NUM>. The regulation unit <NUM> is also arranged in the basement <NUM> of the building <NUM>. The detection unit <NUM> is connected to the regulation unit <NUM> by means of a wired connection <NUM> (e.g. cable). In an alternative embodiment, the wired connection <NUM> may be replaced by a wireless connection that comprises a wireless transmitter connected to the detection unit <NUM> and a wireless receiver connected to the regulation unit <NUM>.

The detection unit <NUM> can be arranged in another location than the one shown in <FIG>. In one embodiment, the detection unit <NUM> is arranged in another location of the building or in a position, in which it is desirable to detect the radon concentration.

The regulation unit <NUM> is connected to the ventilator <NUM> by means of a wired connection <NUM> (e.g. cable). In an alternative embodiment, the wired connection <NUM> is be replaced by a wireless connection that comprises a wireless transmitter connected to the regulation unit <NUM> and a wireless receiver connected to the ventilator <NUM>.

In one embodiment, the regulation unit <NUM> is integrated in the ventilator <NUM>. In one embodiment, the regulation unit <NUM> is a frequency converted arrange configured to control the speed of an electrical motor of the ventilator <NUM>.

The distal portion <NUM> of the guide pipe <NUM> is arranged in a distance from the collecting well <NUM> in order to ensure that the radon-containing air <NUM> is released in a distance from the collecting well <NUM>. Hereby, it is possible to guide the radon-containing air <NUM> away from the collecting well <NUM> and further away from the building.

The end portion of the guide pipe <NUM> is shaped as a bend (U-shaped) structure, wherein the distal portion <NUM> of the guide pipe <NUM> extends downwardly. Hereby, it is possible to avoid rain and other types of precipitation.

<FIG> illustrates a schematic view of a building <NUM> and a system <NUM> shown in <FIG>. The system <NUM> basically corresponds to the one shown in <FIG>. The detection unit and regulation unit shown in <FIG> are, however, not shown in <FIG>. It can be seen that the collecting well <NUM> comprises a cover <NUM> covering the open end of the collecting well <NUM>. The collecting well <NUM> is arranged in a distance from the building <NUM>. Water <NUM> and radon-containing air <NUM> from a drainage system that comprises at least one drainage pipe <NUM> arranged under the building <NUM> are guided into the collecting well <NUM>. The building <NUM> comprises a basement <NUM>.

<FIG> illustrates a further simplified schematic view of another building <NUM> and a system <NUM> shown in <FIG>. The distal end <NUM> of the guide pipe <NUM> is arranged in larger distance L from the collecting well <NUM> than in <FIG> and <FIG>. The distance L may be selected in such a manner that the guide pipe <NUM> can guide away the radon-containing air <NUM> through the guide pipe <NUM> so that the radon-containing air <NUM> is released in a sufficiently large distance L from the building <NUM>. A positive side effect is that, the noise (generated by the ventilator <NUM>, not shown in <FIG> for simplicity) that is hearable inside or in proximity to the building <NUM> is reduced.

<FIG> illustrates a schematic view of a building <NUM> and a system <NUM> according to the invention that basically corresponds to the one shown in <FIG>. The collecting well <NUM> comprises no pipe structure for guiding away excess water from the collecting well <NUM>. This embodiment may be realised when the collecting well <NUM> has a large capacity (volume) or when the collecting well <NUM> is equipped with an alternative member configured to guide away excess water from the collecting well <NUM>. The building <NUM> comprises a basement <NUM>.

<FIG> illustrates a schematic view of an even further building <NUM> and a system <NUM>. The system <NUM> comprises the same elements as the one shown in <FIG>. The system <NUM> furthermore comprises an additional drainage pipe <NUM>' that is attached to a T-branch joint <NUM>' arranged inside the collection well <NUM>. The T-branch joint <NUM>' is connected to the pipe section <NUM>. Hereby, the system <NUM> is configured to receive water <NUM> and radon-containing air <NUM> from both the first drainage pipe <NUM> and the additional drainage pipe <NUM>'. The system <NUM> is configured to and guide away the radon-containing air <NUM> from both first drainage pipe <NUM> and the additional drainage pipe <NUM>' via the pipe section <NUM> and further via the guide pipe <NUM>. The building <NUM> comprises a basement <NUM>.

Claim 1:
System (<NUM>) for removing radon (<NUM>) from a drainage system, wherein the system (<NUM>) comprises a building (<NUM>) and a drainage system that comprises:
- a ventilator (<NUM>);
- a collecting well (<NUM>) and
- a number of drainage pipes (<NUM>) configured for being arranged under a building, wherein the drainage pipes (<NUM>) are arranged under the building (<NUM>), wherein the collecting well (<NUM>) is configured for being installed outside the building,and is arranged outside the building (<NUM>), and wherein the number of drainage pipes (<NUM>) are in fluid communication with the collecting well (<NUM>),
, characterised in that the ventilator (<NUM>) is provided in the collecting well (<NUM>), wherein the ventilator (<NUM>) is connected to one drainage pipe (<NUM>) that extends into the collecting well (<NUM>), wherein said drainage pipe (<NUM>) inclines into the collecting well (<NUM>) to ensure that:
- water (<NUM>) collected by the drainage system is guided into the collecting well (<NUM>) via the drainage pipe (<NUM>) and
- water (<NUM>) and radon (<NUM>) flow through the drainage pipe (<NUM>) into the collecting well (<NUM>).