Respirator fit-testing with size selected aerosol
US6125845A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Aug 29, 1997 |
| Grant date | Oct 3, 2000 |
| Priority date | — |
| Expiry date | Aug 29, 2017 |
Classification
- Technology area (CPC A)Human Necessities
- CPC primaryA62B27/00
- WIPO fieldOther consumer goods
- WIPO sectorOther fields
Abstract
A system and process for respirator fit-testing are disclosed. The system includes conduits for taking first and second aerosol samples, from inside of the respirator mask and from outside of the mask, respectively. The samples are provided to a radial differential mobility analyzer for generating first and second modified samples corresponding to the aerosol samples. The modified samples are provided to a condensation particle counter, which generates first and second concentration values representing concentrations of suspended elements in the respective modified samples. Comparison of the concentration values yields a fit factor indicating how effectively the respirator seals against leaks. Alternative embodiment systems employ a cylindrical DMA, an electrical precipitator, or an inertial separating device in lieu of the radial DMA. For generating concentration values, an electrometer, a photometer or an optical particle counter can be used in lieu of the condensation particle counter. The system facilitates testing in ambient conditions reducing costs and enabling closer simulation of actual working conditions.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.