Apparatus and method for collecting a breath sample using an air circulation system

1. An apparatus for collecting a breath sample, comprising:

a breath input interface configured to receive exhaled breath;

a first conduit system connected to the breath input interface;

a valve configured to control fluid communication between the first conduit system and at least one breath sample storage device configured to store a breath sample;

an air circulation system configured to circulate air through the first conduit system upon completion of a first received exhaled breath; and

at least one controller configured to control the valve upon completion of the first received exhaled breath at least partially based on a humidity level in the first conduit system,

wherein the at least one controller is configured to control the valve at least partially based on whether a change rate in the humidity level is within a humidity level change rate target range.

2. The apparatus of claim 1 , wherein the at least one controller is configured to close the valve to inhibit passage of a subsequent exhaled breath from the first conduit system to the at least one breath sample storage device until the change rate in the humidity level within the first conduit system is within the humidity level change rate target range.

3. The apparatus of claim 2 , further comprising a hygrometer connected to the first conduit system and configured to determine the humidity level in the first conduit system.

4. The apparatus of claim 3 , further comprising a notification system for indicating when the change rate in the humidity level within the first conduit system is within the humidity level change rate target range.

5. The apparatus of claim 3 , wherein the first conduit system includes a breath intake conduit extending between the breath input interface and the valve, and wherein the hygrometer is connected to an exhaust conduit of the first conduit system that branches from the breath intake conduit.

6. The apparatus of claim 5 , wherein the fluid circulation system is directly connected to the exhaust conduit.

7. The apparatus of claim 6 , wherein the exhaust conduit includes a flow meter configured to measure a flow rate along the exhaust conduit.

8. The apparatus of claim 1 , wherein the at least one controller is configured to control the valve at least partially based on whether the humidity level is within a humidity level target range.

9. The apparatus of claim 8 , wherein the at least one controller is configured to close the valve to inhibit passage of a subsequent exhaled breath from the first conduit system to the at least one breath sample storage device until the humidity level within the first conduit system is within the humidity level target range.

10. A method for collecting a breath sample, comprising:

receiving an exhaled breath via a breath input interface connected to a first conduit system;

collecting at least some of the exhaled breath via at least one breath sample storage device connected to the first conduit system;

detecting a completion of the exhaled breath;

closing a valve between the first conduit system and the at least one breath sample storage device upon detecting the completion of the exhaled breath;

circulating air through a first conduit system connected to the breath input interface after detecting the completion of the exhaled breath;

monitoring a humidity level in the first conduit system;

determining if a change rate in the humidity level is within a humidity level change rate target range; and

controlling, via at least one controller, the valve at least partially based on the humidity level in the first conduit system.

11. The method of claim 10 , further comprising controlling the valve to close to inhibit passage of a subsequently exhaled breath from the first conduit system to the at least one breath sample storage device until the change rate in the humidity level within the first conduit system is within the humidity level change rate target range.

12. The method of claim 11 , further comprising determining the humidity level in the first conduit system via a hygrometer connected to the first conduit system.

13. The method of claim 12 , further comprising indicating when the change rate in the humidity level is within the humidity level change rate target range.

14. The method of claim 12 , wherein the first conduit system includes a breath intake conduit extending between the breath input interface and the valve, and wherein the determining of the humidity level is performed by a hygrometer connected to an exhaust conduit of the first conduit system that branches from the breath intake conduit.

15. The method of claim 14 , wherein the fluid circulation system is directly connected to the exhaust conduit.

16. The method of claim 15 , further comprising measuring a flow rate along the exhaust conduit via a flow meter along the exhaust conduit.

17. The method of claim 10 , wherein the controlling includes determining if the humidity level is within a humidity level target range.

18. The method of claim 17 , further comprising controlling the valve to close to inhibit passage of a subsequently exhaled breath from the first conduit system to the at least one breath sample storage device until the humidity level within the first conduit system is within the humidity level target range.