US4269804A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Self-contained gaseous contaminant dosimeter
Assignee: PRO-TEK SYSTEMS Inc
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Filing: 1979-12-03
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Granted: 1981-05-26
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Expires: 1999-12-03
Abstract
Abstract A personal dosimeter for measuring the average concentration of a gaseous contaminant over a given period of time is provided. The dosimeter comprises a sealed pouch having a reaction chamber, which contains a gas-collecting medium, and at least one compartment. Each compartment can be separately sealed and can contain a different reagent, the seals being individually breakable such that the reagents can be separately released into the reaction chamber. Into the pouch is sealed a gas diffusion device that permits the contaminant to diffuse into the reaction chamber where it is collected in proportion to its ambient concentration.
Inventors
- 👤 Elbert V. Kring
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-10-25 00:21
CPC Classifications
G; G01; G01N; G01N31/00; G01N31/22; G01N31/223; Y; Y10; Y10S; Y10S436/00; Y10S436/902; Y10T; Y10T436/00; Y10T436/17; Y10T436/173845; Y10T436/175383; Y10T436/177692; Y10T436/178459; Y10T436/18; Y10T436/186
Claims Analysis
Total Claims: 12
Claim 1
Independent Claim
137 words
A personal dosimeter for measuring the average concentration of a gaseous contaminant over a given period of time comprising: a pouch-like receptacle of polymeric material having at least one compartment, the compartment occupying less than the total volume of the receptacle, leaving a reaction chamber, the compartment containing a pre-determined quantity of a color-forming reagent and being adapted to release the reagent into the reaction chamber independently of any other reagents present in any other compartments, and the reaction chamber containing a collecting medium for the gaseous contaminant; and a gas diffusion device which is sealed into a boundary of the receptacle and through which the contaminant diffuses at a rate in linear proportion to its concentration in the atmosphere, the diffusion device providing the only communication between the atmosphere and the interior of the reaction chamber.
Claim 2
Dependent Claim
137 words
A personal dosimeter for measuring the average concentration of a gaseous contaminant over a given period of time comprising: a pouch-like receptacle of polymeric material having at least one compartment, the compartment occupying less than the total volume of the receptacle, leaving a reaction chamber, the compartment containing a pre-determined quantity of a color-forming reagent and being adapted to release the reagent into the reaction chamber independently of any other reagents present in any other compartments, and the reaction chamber containing a collecting medium for the gaseous contaminant; and a gas diffusion device which is sealed into a boundary of the receptacle and through which the contaminant diffuses at a rate in linear proportion to its concentration in the atmosphere, the diffusion device providing the only communication between the atmosphere and the interior of the reaction chamber.
Claim 3
Dependent Claim
23 words
The dosimeter of claim 1 in which the gas diffusion device contains a plurality of through-and-through channels by which said communication is provided.
Claim 4
Dependent Claim
24 words
The dosimeter of claim 2 in which there are 5-500 channels, each having a diameter of 50-1000 microns and a length of 1.0-25.0 mm.
Claim 5
Dependent Claim
32 words
The dosimeter of claim 1 in which the gas diffusion device is a membrane through which the gaseous contaminant passes at a rate in linear proportion to its concentration in the atmosphere.
Claim 6
Dependent Claim
21 words
The dosimeter of claim 4 in which the membrane is constructed of silicone rubber, polytetrafluoroethylene, or copolymers of silicone and polycarbonate.
Claim 7
Dependent Claim
22 words
The dosimeter of claim 1, 2, 3, 4, or 5 wherein the collecting medium is in the form of an absorbing solution.
Claim 8
Dependent Claim
17 words
The dosimeter of claim 6 wherein the absorbing solution is for sulfur dioxide, nitrogen dioxide, or ammonia.
Claim 9
Dependent Claim
12 words
The dosimeter of claim 7 further containing at least one color-forming reagent.
Claim 10
Dependent Claim
31 words
The dosimeter of claim 8 wherein the absorbing solution is a solution of sodium tetrachloromercurate or potassium tetrachloromercurate in water and the reagent is for determining the presence of sulfur dioxide.
Claim 11
Dependent Claim
28 words
The dosimeter of claim 8 wherein the absorbing solution is a solution of triethanol amine in water and the reagent is for determining the presence of nitrogen dioxide.
Claim 12
Dependent Claim
27 words
The dosimeter of claim 8 wherein the absorbing solution is a solution of sulfuric acid in water and the reagent is for determining the presence of ammonia.
References Cited (Backward Citations)
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US3726645A
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US4137049A
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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) | 1984-05-25 | 1984-11-24 | 1985-05-26 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1988-05-25 | 1988-11-24 | 1989-05-26 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1992-05-25 | 1992-11-24 | 1993-05-26 | $7700.00 | Window Closed / Lapsed |