Patent Application
20190277002
The present invention relates to systems and methods for mitigating radon, and more particularly, embodiments concern a system and method for selecting proper components, particularly a proper fan, for mitigating the presence of radon gas in a building or other structure.
Radon is a naturally occurring radioactive, colorless, odorless, and tasteless gas. Radon is a health hazard and is often the single largest contributor to individuals' background radiation dose, and breathing high concentrations of radon has been linked to lung cancer. Due to local differences in geology, the hazard of radon varies from location to location. Radon can accumulate in buildings, where because of its relatively high density, it generally accumulates in lower areas such as basements and crawl spaces. Thus, it is often desirable to detect and mitigate the presence of radon.
One method of mitigating radon in a residential building is to depressurize a foundation slab of the building using an inline fan and polyvinyl chloride (PVC) pipes for ducting. However, because soil conditions and building sizes vary, determining the exact negative pressure required for a particular job can be difficult. Currently, radon mitigators rely on rough estimates of areas and past experience to size their systems, but it is not uncommon for mitigators to have to return to jobs, sometimes more than once, and upgrade the fans to meet the static pressure requirements through a process of trial and error. Some mitigators initially install oversized fans so that they do not have to return to jobs, but this unnecessarily increases cost and power consumption.
This background discussion is intended to provide information related to the present invention which is not necessarily prior art.
Embodiments address the above-described and other problems by providing a system and method for selecting proper components, particularly a proper fan, for mitigating the presence of radon gas in a building or other structure.
In a first embodiment, a system is provided for facilitating the selection of a proper fan for an air flow system for mitigating radon in a particular structure. The particular structure may broadly have a foundation slab and the airflow system. The air flow system may include a lower pipe in communication with an access hole extending through an approximate center of the foundation slab and into a soil beneath the foundation slab; an upper pipe connecting the lower pipe to an exterior area above the particular structure; and a test hole extending through the foundation slab at a location which is spaced apart from the access hole. The system may broadly comprise a test fan, a manometer, and a visual tool and/or a computer program. The test fan may be installed along the pipe assembly, wherein the test fan may be a variable speed fan having a known performance curve. The manometer may be configured to measure a static pressure value as a pressure differential across the test fan.
The visual tool may be configured to correlate a particular speed of the test fan and a particular static pressure value when operation of the test fan creates an initial draw of air due to a negative pressure under the foundation slab at the test hole with an identification of a proper fan from among a plurality of possible fans. The proper fan may have an operating speed which is closest to the particular speed, and may be installed in place of the test fan in the air flow system for mitigating radon in the particular structure.
The computer program may be executed on a mobile computing device and configured to receive as input the particular speed of the test fan and the particular static pressure when operation of the test fan creates the initial draw of air due to negative pressure under the foundation slab at the test hole; identify the proper fan from among the plurality of possible fans based on the input, wherein the proper fan has the operating speed which is closest to the particular speed; and output the identification of the proper fan to be installed in place of the test fan in the air flow system for mitigating radon in the particular structure.
Various implementations of the first embodiment may include any one or more of the following features. The visual tool may include first data representing behavior of the test fan operating at different speeds, and second data representing behavior of an overall system resulting in different static pressure values, wherein an intersection of the first data and the second data provides a basis for identifying the proper fan from among the plurality of possible fans. The visual tool may be a chart, and the first data may be presented as a first plotted line, and the second data may be presented as a second plotted line. The proper fan may be operable to run only at the operating speed, or the proper fan may be operable to run at two or more speeds including the operating speed. The mobile computing device may be a mobile laptop or tablet computer, or a smartphone.
In a second embodiment, a method is provided for facilitating the selection of a proper fan for mitigating radon in a particular structure having a foundation slab. The method may broadly comprise the following. An air flow system may be installed including a pipe assembly including a lower pipe in communication with an access hole extending through an approximate center of the foundation slab and into a soil beneath the structure, and an upper pipe connecting the lower pipe to an exterior area above the particular structure. A test hole may be created extending through the foundation slab at a location which is spaced apart from the access hole. A test fan may be installed along the pipe assembly, wherein the test fan is a variable speed fan having a known performance curve. A manometer may be installed configured to measure a static pressure value as a pressure differential across the test fan. A computer program may be executed on a mobile computing device and configured to receive as input a particular speed of the test fan and a particular static pressure value when operation of the test fan creates an initial draw of air due to negative pressure under the foundation slab at the test hole; identify a proper fan from among a plurality of possible fans based on the input, wherein the proper fan has an operating speed which is closest to the particular speed; and output an identification of the proper fan. The test fan may be removed and the proper fan may be installed in the pipe assembly for mitigating radon in the particular structure.
Various implementations of the second embodiment may include any one or more of the following features. The mobile computing device may be a mobile laptop or tablet computer, or a smartphone. The proper fan may be operable to run only at the operating speed, or the proper fan may be operable to run at two or more speeds including the operating speed.
This summary is not intended to identify essential features of the present invention, and is not intended to be used to limit the scope of the claims. These and other aspects of the present invention are described below in greater detail.
Embodiments of the present invention are described in detail below with reference to the attached drawing figures, wherein:
The figures are not intended to limit the present invention to the specific embodiments they depict. The drawings are not necessarily to scale.
The following detailed description of embodiments of the invention references the accompanying figures. The embodiments are intended to describe aspects of the invention in sufficient detail to enable those with ordinary skill in the art to practice the invention. The embodiments of the invention are illustrated by way of example and not by way of limitation. Other embodiments may be utilized and changes may be made without departing from the scope of the claims. The following description is, therefore, not limiting. The scope of the present invention is defined only by the appended claims, along with the full scope of equivalents to which such claims are entitled.
In this description, references to “one embodiment,” “an embodiment,” or “embodiments” mean that the feature or features referred to are included in at least one embodiment of the invention. Separate references to “one embodiment,” “an embodiment,” or “embodiments” in this description do not necessarily refer to the same embodiment and are not mutually exclusive unless so stated. Specifically, a feature, component, action, step, etc. described in one embodiment may also be included in other embodiments, but is not necessarily included. Thus, particular implementations of the present invention can include a variety of combinations and/or integrations of the embodiments described herein.
Broadly characterized, embodiments concern a system and method for selecting proper components, particularly a proper fan, for mitigating the presence of radon gas in a building or other structure. Embodiments advantageously match the fan component to the particular requirements of a particular job, thereby eliminating the temptation to install a fan that is too large for the job, which saves money, while also eliminating the need to return to the particular job in order to upgrade a fan that is too small, which saves both time and money.
Referring to
The test hole 18 may be located spaced apart from the access hole 24, and may also extend through the slab 26. In one implementation, the test hole 18 may be located spaced as far apart as practically possible from the access hole 24. The proper fan 20 may be installed in substantially any suitable location along the pipe assembly 16, such as between the lower pipe 22 and the upper pipe 30. The proper fan 20 may be an inline fan, and the proper fan 20 may be a single speed fan operable to run at one speed, or it may be a multi-speed fan operable to run at multiple speeds.
The air flow system 10 may be configured to depressurize the slab 26 of the structure 12 so as to draw any radon gas 14 into the lower pipe 22 and through the upper pipe 30 so it can be vented to the exterior area. Depressurization involves creating a required negative pressure which is a function of several factors of the overall system, such as the condition of the soil 28 beneath the slab 26 and the size of the structure 12.
Referring to
In
Once the performance behavior of the test fan 112 at maximum speed is determined experimentally, the performance behavior at other speeds (e.g., at 10% intervals) can be calculated using the First Fan Law. Similarly, once the behavior of the overall system at maximum speed is determined experimentally, the behavior of the overall system at other speeds can be calculated using the Second Fan Law.
In one implementation, the airflow system 10 may be considered distinct from the system 110, while in another implementation, the airflow system 10 may be considered part of or an extension of the system 10.
Referring to
The speed of the test fan 112 may be adjusted until there is only initial communication between the test fan 112 and the test hole 18 (i.e., an initial draw at the test hole 18 due to negative pressure under the slab 26), as shown in 220. As used herein, “initial communication” and “initial draw” shall mean a measurable or otherwise detectable and consistent air flow at the test hole 18 (e.g., a negative pressure of at least two one-hundredths of an inch (−0.02″) water column. Although higher negative pressure is permissible, it may be desirable to avoid “overpowering” the motor, and only a noticeable flow is required. The corresponding particular speed of the test fan 112 at which this initial communication occurs, and the corresponding particular static pressure value of the overall system measured with the manometer 114 as the pressure differential across the test fan 112, may be noted.
In a chart implementation, a visual tool, such as the charts 122,132,142 or corresponding tables, may be configured to correlate the particular speed of the test fan 112 and the particular static pressure value of the overall system with an identification of a proper fan 20 from among a plurality of available fans, as shown in 222, wherein the proper fan 20 has an operating speed which is closest to (and preferably without being under) the particular speed. In an additional or alternative computer program implementation, a computer program may be executed on a laptop, tablet, smartphone or other mobile computing device, and receive as input the particular speed of the test fan 112 and the particular static pressure value of the overall system, as shown in 224. The computer program may identify the proper fan 20 from among a plurality of available fans based on the input, as shown in 226, wherein the proper fan 20 has an operating speed which is closest to (and preferably without being under) the particular speed. The computer program may output an identification of the proper fan 20, as shown in 228. The test fan 112 may then be removed and the proper fan 20 may be installed in the pipe assembly 16 for mitigating radon in the exemplary particular structure 12, as shown in 130.
The system 10 may include more, fewer, or alternative components and/or perform more, fewer, or alternative actions, including those discussed elsewhere herein, and particularly those discussed in the following section describing the method.
Referring again to
The test hole 18 may be created extending through the slab 26 at a location which is spaced apart from the access hole 24, as shown in 214. The test fan 112 may be installed in the pipe assembly 16 (e.g., between the lower pipe 22 and the upper pipe 30), as shown in 216, wherein the test fan 112 is a variable speed fan having a known performance curve. The manometer 114 may be installed, as shown in 218, wherein the manometer 114 is configured to measure a static pressure value as a pressure differential across the test fan 112.
The speed of the test fan 112 may be adjusted until there is only initial communication between the test fan 112 and the test hole 18 (i.e., an initial draw at the test hole 18 due to negative pressure under the slab 26), as shown in 220. The corresponding particular speed of the test fan 112 at which this initial communication occurs, and the corresponding particular static pressure value of the overall system measured with the manometer 114 as the pressure differential across the test fan 112, may be noted. For example, the operating speed may be thirty (30) percent of the maximum speed of the test fan 112 and the static pressure may be three and one-half (3.5) inches of water column.
In a chart implementation, a visual tool, such as the charts 122,132,142 or corresponding tables, may be configured to correlate the particular speed of the test fan 112 and the particular static pressure value of the overall system with an identification of a proper fan 20 from among a plurality of available fans, as shown in 222, wherein the proper fan 20 has an operating speed which is closest to the particular speed. It may be desirable for the proper fan to have an operating speed that is equal to or greater than the particular speed. More specifically, the visual tool may include first data representing the behavior of the test fan 112 operating at different speeds, and second data representing the behavior of the overall system resulting in different static pressure values, and an intersection of the first data and the second data may determine a working point or provide another basis for identifying the proper fan 20 from among the plurality of available fans.
In an additional or alternative computer program implementation, a computer program may be executed on a laptop, tablet, smartphone or other mobile computing device, and receive as input the particular speed of the test fan 112 and the particular static pressure value of the overall system, as shown in 224. The computer program may automatically identify the proper fan 20 from among a plurality of available fans based on the input, as shown in 226, wherein the proper fan 20 has an operating speed which is closest to (and preferably without being under) the particular speed. The computer program may output an identification of the proper fan 20, as shown in 228. The test fan 112 may then be removed and the proper fan 20 may be installed in the air flow assembly 10 for mitigating radon in the exemplary particular structure 12, as shown in 230.
The computer-implemented method 210 may include more, fewer, or alternative actions, including those discussed elsewhere herein.
Although the invention has been described with reference to the one or more embodiments illustrated in the figures, it is understood that equivalents may be employed and substitutions made herein without departing from the scope of the invention as recited in the claims.
Having thus described one or more embodiments of the invention, what is claimed as new and desired to be protected by Letters Patent includes the following:
