Method and apparatus for sealing building ductwork during chemical or biological attack
US6217441A · kind A · utility
Assignee
Inventors
Key dates
| Filing date | Mar 30, 1999 |
| Grant date | Apr 17, 2001 |
| Priority date | — |
| Expiry date | Mar 30, 2019 |
Classification
- Technology area (CPC Y)Emerging Cross-Sectional Technologies
- CPC primaryY10S454/902
- WIPO fieldThermal processes and apparatus
- WIPO sectorMechanical engineering
Abstract
A system for sealing a building air duct in response to a chemical or biological attack to prevent the building HVAC system from delivering the chemical or biological agent throughout the building. The system can include an inflatable bladder for disposition within an air duct, a source of gas for expanding the bladder, an initiator for initiating the gas expansion, and a detector for detecting the agent. One bladder is formed of a resilient material suitable for extending into duct corners. Another bladder is larger than the duct to be sealed and is formed of a non-resilient material capable of inflating and bunching into duct corners. One source of gas is a gas canister while another source of gas is a chemical composition capable of reacting and forming the gas. One bladder includes a foaming agent which can expand and solidify within the bladder. One initiator utilizes an electronic signal to initiate the gas expansion. Another initiator includes use of an RF signal to initiate the gas expansion. One agent detector samples duct air while another detector includes a horizon detector for detecting agents in the air outside the building.
Source: USPTO / EPO open patent data. Objective bibliographic and citation counts.