Ventilation system for a protective suit

• US 20030024529A1
• Filed: 07/22/2002
• Published: 02/06/2003
• Est. Priority Date: 04/03/2000
• Status: Active Grant

• Current Assignee: Safety Equipment Sweden AB (Gifa AB)
• Original Assignee: Safety Equipment Sweden AB (Gifa AB)
• Inventors: Beizndtsson, Goran B.C., Backman, Lennart
• Granted Patent: US 6,837,239 B2
• Time in Patent Office: Days
• US Class Current: 128/201.29
• CPC Class Codes: A62B 17/005 Active or passive body temperature control
• CPC Class Codes: A62B 17/006 against contamination from chemicals, toxic or hostile environments; ABC suits

Abstract

The present invention relates to a ventilation system for a protective suit for use in hazardous environments. In a further aspect it concerns the protective suit itself. An air purifying respirator draws air from outside the protective suit through a filter, supplies filtered breathing air via a breathing hose to a space within the face piece, and supplies filtered ventilating air via a ventilating hose to the interior of the protective suit. A ventilation valve in the ventilating hose automatically closes only during periods of high breathing demand to counter a pressure drop inside the face piece.

Claims

1. A ventilation system for a protective suit, including in combination:

a protective suit to cover the user'"'"'s body;

a face piece to cover at least the nose or mouth of the user;

an air purifying respirator to draw air from outside the protective suit through a filter, and to supply filtered breathing air via a breathing hose to a space within the face piece, and to supply filtered ventilating air via a ventilating hose to the interior of the protective suit;

a ventilation valve in the ventilating hose automatically operable to close the ventilation valve only during periods of high breathing demand to counter a pressure drop inside the face piece.

2. A ventilation system according to claim 1, where the valve closes when the pressure drop across the filter exceeds a predetermined value, the flow rate exceeds a predetermined value, or the pressure inside the mask falls below a predetermined value, or the pressure inside the mask falls below a predetermined value, or any combination of these parameters.

3. A ventilation system according to claim 1, further including a processor to receive signals from sensors associated with the system, and control the automatic operation of the ventilation valve.

4. A ventilation system according to claim 3, where the signals received from the sensors include a signal representing the pressure drop across the filter, the air flow rate through the respirator or the breathing hose, or the air pressure inside the mask.

5. A ventilation system according to any preceding claim, where the valve operates between two states.

6. A ventilation system according to claim 5, where the valve operates progressively between the two states.

7. A ventilation system according to claim 1, where the air purifying respirator operates to respond to breathing demand and increase flow to the face piece when breathing demand increases.

8. A ventilation system according to claim 1, where the air purifying respirator is worn in a harness and is positioned inside the back of the protective suit where space is provided by an extension.

9. A ventilation system according to claim 8, where a port is provided in the extension for air to be drawn in from outside the protective suit by the air purifying respirator.

10. A ventilation system according to claim 9, where the filter is outside the suit and screwed to a spigot extending from the pump unit through the port.

12. A gas tight protective suit according to claim 11, incorporating a ventilation system according to any one of claims 1 to 10.

11. A gas tight protective suit to cover a user'"'"'s body, comprising:

a rear extension to house a pump unit worn in a harness, and a port in the extension for air to be drawn in from outside the protective suit by an air purifying respirator;

an air-tight connection being made around the port when a filter is properly connected to the pump unit so that no air may pass through the port without passing through the filter.