US3698871A
Expired / Lapsed
US
⏱️ 0.0 years remaining
Air pollution detectors
Assignee: Individual
•
Filing: 1970-04-16
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Granted: 1972-10-17
•
Expires: 1990-04-16
Abstract
Abstract AN EASILY SEEN, STANDARDIZED SURFACE, SUCH AS THAT OF A MAST, MOUNTED IN THE EFFLUENT DISCHARGING FROM A POTENTIAL SOURCE OF AIR POLLUTION, SUCH AS A CHIMMEY, TO PROVIDE A VISIBLE SURFACE ON WHICH CAN BE ACCUMULATED AN INFORMATIVE RECORD OF THE CONDITION OF THE EFFLUENT, SINCE THE DEVICE WAS INSTALLED.
Inventors
- 👤 George Andrew Brennan
Bibliographic Details
Application Number
—
Jurisdiction
US
Data Source
google_patents
Last Synchronized
2026-11-02 10:51
CPC Classifications
G; G01; G01N; G01N33/00; G01N33/0004; G01N33/0009; G01N33/0027; Y; Y10; Y10T; Y10T436/00; Y10T436/17; Y10T436/173845; Y10T436/175383; Y10T436/177692; Y10T436/18; Y10T436/186
Claims Analysis
Total Claims: 0
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References Cited (Backward Citations)
No citation records indexed.
USPTO Annuity & Maintenance Windows
| Annuity Stage | Window Opens | Payment Deadline | Surcharge Period Until | Estimated Fee | Status |
|---|---|---|---|---|---|
| 3.5 Years (Year 4) | 1975-10-17 | 1976-04-17 | 1976-10-17 | $2000.00 | Window Closed / Lapsed |
| 7.5 Years (Year 8) | 1979-10-17 | 1980-04-17 | 1980-10-17 | $3760.00 | Window Closed / Lapsed |
| 11.5 Years (Year 12) | 1983-10-17 | 1984-04-17 | 1984-10-17 | $7700.00 | Window Closed / Lapsed |