US4975575A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Method of and apparatus for detecting radon
Assignee: PROFESSIONAL LABORATORIES Inc
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Filing: 1987-09-11
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Granted: 1990-12-04
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Expires: 2007-09-11
Abstract
Abstract A method of and apparatus for measuring radon concentration in air involving the provision of a detector containing an adsorbent of radon and a desiccant. The desiccant can selectively retain an amount of water weighing from about 25% to about 50% of the weight of the adsorbent. The detector is exposed to a finite air space to be measured for a predetermined time period. The radon is liberated from the adsorbent so that the alpha particles and beta particles, which are the signature of radon radioactivity, are counted by liquid scintillation technique. The air may be pumped through the apparatus to hasten the radon adsorption process.
Inventors
- 👤 Daniel Perlman
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-30 12:10
CPC Classifications
G; G01; G01T; G01T1/00; G01T1/16; G01T1/17; G01T1/178; G01T7/00; G01T7/02; Y; Y10; Y10S; Y10S250/00; Y10S250/02
Claims Analysis
Total Claims: 23
Claim 1
Independent Claim
59 words
A radon detection device comprising: an equilibrium adsorption material for monitoring radon level, a gas permeable holding means for said adsorption material, an air pump for propelling ambient atmosphere through said adsorption material positioned in said holding means, and a gas flow connecting means by which said ambient atmosphere flows through said air pump connected to said adsorption material.
Claim 2
Dependent Claim
59 words
A radon detection device comprising: an equilibrium adsorption material for monitoring radon level, a gas permeable holding means for said adsorption material, an air pump for propelling ambient atmosphere through said adsorption material positioned in said holding means, and a gas flow connecting means by which said ambient atmosphere flows through said air pump connected to said adsorption material.
Claim 3
Dependent Claim
52 words
A radon detection device according to claim 1 wherein a desiccant material and desiccant holding means are included in said device to remove ambient moisture from the pumped atmosphere and wherein said desiccant and said holding means are connected in series with and upstream with respect to the flow of the atmosphere.
Claim 4
Dependent Claim
14 words
A detection device according to claim 1 wherein said adsorption material is activated charcoal.
Claim 5
Dependent Claim
18 words
A detection device according to claim 2 wherein said desiccant is silica gel or anhydrous CaSO 4 .
Claim 6
Dependent Claim
36 words
A detection device according to claim 1 wherein said adsorption material is activated charcoal and said charcoal is in the form of granules whose average diameter is greater than 0.5 mm and less than 5 mm.
Claim 7
Dependent Claim
50 words
A detection device according to claim 1 wherein said holding means is a walled container having porous or mesh-like ends wherein said pores or mesh holes are sufficiently large to allow rapid continuous gas flow and sufficiently small to prevent the charcoal from exiting through said pores or mesh holes.
Claim 8
Dependent Claim
92 words
A radon detection device comprising: an equilibrium adsorption material for monitoring radon level, a gas permeable holding means for said adsorption material, an air pump for propelling ambient atmosphere through said adsorption material positioned in said holding means, a desiccant material and desiccant holding means to remove ambient moisture from the pumped atmosphere, said holding means being connected in series with and upstream with respect to the flow of the atmosphere, and a gas flow connecting means by which said ambient atmosphere flows through said air pump connected to said adsorption material.
Claim 9
Dependent Claim
92 words
A radon detection device comprising: an equilibrium adsorption material for monitoring radon level, a gas permeable holding means for said adsorption material, an air pump for propelling ambient atmosphere through said adsorption material positioned in said holding means, a desiccant material and desiccant holding means to remove ambient moisture from the pumped atmosphere, said holding means being connected in series with and upstream with respect to the flow of the atmosphere, and a gas flow connecting means by which said ambient atmosphere flows through said air pump connected to said adsorption material.
Claim 10
Independent Claim
67 words
A method for the active sampling of radon including the steps of: assembling a container of equilibrium adsorption material, placing said container within a building or other finite volume of air, forcing said air through said container for a period of time sufficient to equilibrate the radon adsorbent in said container with respect to the radon in said air, and counting the radioactivity in said adsorption material.
Claim 11
Independent Claim
67 words
A method for the active sampling of radon including the steps of: assembling a container of equilibrium adsorption material, placing said container within a building or other finite volume of air, forcing said air through said container for a period of time sufficient to equilibrate the radon adsorbent in said container with respect to the radon in said air, and counting the radioactivity in said adsorption material.
Claim 12
Dependent Claim
17 words
The method of claim 8 wherein the radioactivity from said adsorbent is detected using liquid scintillation counting.
Claim 13
Dependent Claim
17 words
The method of claim 8 wherein the radioactivity from said adsorbent is detected using gamma ray counting.
Claim 14
Dependent Claim
66 words
A passive diffusion device for measuring the radioactive radon concentration in ambient air comprising: a container in the form of an airtight vial having at least one diffusion opening, a predetermined amount of radon adsorbent and a desiccant in the container, the container being translucent to photons produced from liquid scintillant added to the container after the adsorbent has been exposed to ambient air containing radon.
Claim 15
Dependent Claim
66 words
A passive diffusion device for measuring the radioactive radon concentration in ambient air comprising: a container in the form of an airtight vial having at least one diffusion opening, a predetermined amount of radon adsorbent and a desiccant in the container, the container being translucent to photons produced from liquid scintillant added to the container after the adsorbent has been exposed to ambient air containing radon.
Claim 16
Dependent Claim
14 words
A diffusion device according to claim 11 wherein the air-tight vial is a polyolefin.
Claim 17
Dependent Claim
15 words
A diffusion device according to claim 11 wherein the air-tight vial has a removable cap.
Claim 18
Dependent Claim
21 words
A diffusion device according to claim 11 wherein the adsorbent is in a gas and liquid permeable member with the container.
Claim 19
Dependent Claim
62 words
A passive diffusion device for collecting and allowing measurement of the radioactive radon concentration in air, comprising: an adsorbent of radon within an airtight scintillation vial, a desiccant in the vial juxtaposed relative to said adsorbent, the vial being transulucent to scintillation photons so that said photons, which are a measure of said radon, may be counted by a scintillation counting instrument.
Claim 20
Dependent Claim
62 words
A passive diffusion device for collecting and allowing measurement of the radioactive radon concentration in air, comprising: an adsorbent of radon within an airtight scintillation vial, a desiccant in the vial juxtaposed relative to said adsorbent, the vial being transulucent to scintillation photons so that said photons, which are a measure of said radon, may be counted by a scintillation counting instrument.
Claim 21
Dependent Claim
27 words
The device of claim 15 wherein the desiccant is effective in reducing moisture, being effective both in free granular form as well as in porous packaged form.
Claim 22
Dependent Claim
140 words
In a passive diffusion device for measuring the radioactive radon concentration in ambient air having and adsorbent of radon in a container with one or more diffusion openings, the improvement comprising: juxtaposing the adsorbent with a desiccant, the desiccant being present in a sufficient quantity to keep the adsorbent substantially moisture-free for between 1 day and 1 week during exposure to radon under relative humidity conditions ranging from 0 to 100%, the juxtaposed desiccant being placed in close proximity with the adsorbent so that the ambient air, carrying radioactive radon, can enter the adsorbent and the weitht of desiccant is sufficient to remove moisture out of the adsorbent during the periord of exposure of the device to the embient air, and said desiccant being effective in removing moisture when in both free granular forms as well as porous packaged form.
Claim 23
Dependent Claim
140 words
In a passive diffusion device for measuring the radioactive radon concentration in ambient air having and adsorbent of radon in a container with one or more diffusion openings, the improvement comprising: juxtaposing the adsorbent with a desiccant, the desiccant being present in a sufficient quantity to keep the adsorbent substantially moisture-free for between 1 day and 1 week during exposure to radon under relative humidity conditions ranging from 0 to 100%, the juxtaposed desiccant being placed in close proximity with the adsorbent so that the ambient air, carrying radioactive radon, can enter the adsorbent and the weitht of desiccant is sufficient to remove moisture out of the adsorbent during the periord of exposure of the device to the embient air, and said desiccant being effective in removing moisture when in both free granular forms as well as porous packaged form.
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USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1993-12-03 | 1994-06-04 | 1994-12-04 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1997-12-03 | 1998-06-04 | 1998-12-04 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 2001-12-03 | 2002-06-04 | 2002-12-04 | $7700.00 | Window Closed / Lapsed |