Method for adjusting airflow in a rodent containment cage

1. A method for adjusting airflow in a rodent containment cage to a set level, which comprises:

ventilating the rodent containment cage with a blower assembly connected to the rodent containment cage with an air supply conduit, air exhaust conduit or both an air supply conduit and air exhaust conduit;

sensing air pressure with an air pressure sensor disposed in the air supply conduit or air exhaust conduit connected to the animal cage wherein the sensor sends an air pressure signal directly to a controller;

comparing the sensed air pressure to a set level of air pressure by the controller; and

increasing or decreasing the speed of one or more fans in the blower assembly until the air pressure reaches the set level, wherein the controller slows the response rate for increasing or decreasing the speed of the one or more fans when the air pressure signal sent by the sensor to the controller is near the set level.

2. The method of claim 1 , wherein the blower assembly comprises two or more fans in series with a common flow direction relative to the rodent containment cage and with the air leaving one fan entering the intake of another fan and a fan motor separately driving each fan and wherein the speed of the two or more fans in series is increased or decreased.

3. The method of claim 2 further comprising monitoring blower rotation per minute signals during operation of the blower assembly.

4. The method of claim 3 further comprising maintaining different rotations per minute for the two or more fans of the blower assembly.

5. The method of claim 1 , wherein increasing or decreasing the speed of one or more fans in a blower assembly comprises delaying the increase or decrease of the speed of one or more fans after sensing and comparing the pressure, with an amount of the delay of the increase or decrease configured to prevent substantial swings in airflow.

6. The method of claim 1 wherein the blower assembly comprises a mixing box configured to render airflow of an HVAC system substantially constant and further comprising removing exhaust air from the mixing box through a heating, ventilation or air conditioning HVAC system.

7. The method of claim 1 further comprising emitting an audible alarm when the pressure within the rodent containment cage deviates at a specified increment from the set level.

8. The method of claim 1 wherein ventilating the rodent containment cage with the blower assembly comprises forcing supply air into the rodent containment cage.

9. The method of claim 1 wherein ventilating the rodent containment cage with the blower assembly comprises drawing exhaust air out of the rodent containment cage.

10. A method for adjusting airflow in a rodent containment cage, which comprises:

ventilating the rodent containment cage with a blower assembly connected to the rodent containment cage comprising two or more fans which are each disposed in a separate blower housing in series with a common flow direction relative to the rodent containment cage and with the exhaust of one fan entering the intake of another fan and a fan motor separately driving each fan;

sensing airflow with a sensor disposed in the rodent containment cage or an air supply conduit or air exhaust conduit connected thereto wherein the sensor sends an air pressure signal directly to a controller;

comparing the sensed airflow to a set level by the controller; and

increasing or decreasing the speed of one or more fans in the blower assembly until the airflow reaches the set level, wherein the controller slows the response rate for increasing or decreasing the speed of the one or more fans when the air pressure signal sent by the sensor to the controller is near the set level.

11. The method of claim 10 , further comprising monitoring blower rotation per minute signals during operation of the blower assembly.

12. The method of claim 10 further comprising maintaining different rotations per minute for the two or more fans of the blower assembly.

13. The method of claim 10 wherein increasing or decreasing the speed of one or more fans in a blower assembly comprises delaying the increase or decrease of the speed of one or more fans after sensing and comparing the airflow, with an amount of the delay of the increase or decrease configured to prevent substantial swings in airflow.

14. The method of claim 10 wherein the blower assembly further comprises a mixing box configured to render airflow of an HVAC system substantially constant and further comprising removing containment cage exhaust air from the mixing box through a heating, ventilation or air conditioning HVAC system.

15. The method of claim 10 further comprising emitting an audible alarm when the airflow within the rodent containment cage deviates at a specified increment from the set level.

16. The method of claim 10 wherein ventilating the rodent containment cage with the blower assembly comprises forcing supply air into the rodent containment cage.

17. The method of claim 10 wherein ventilating the rodent containment cage with the blower assembly comprises drawing exhaust air out of the rodent containment cage.

18. A method for adjusting airflow in a rodent containment cage, which comprises:

ventilating the rodent containment cage with a blower assembly connected to the rodent containment cage comprising two or more fans which are each disposed in a separate blower housing in series with a common flow direction relative to the rodent containment cage and with the exhaust of one fan entering the intake of another fan and a fan motor separately driving each fan; and

increasing or decreasing the speed of the two or more fans in the blower assembly while controlling the two or more fans to have different speeds, wherein a controller slows the response rate for increasing or decreasing the speed of the one or more fans when the air pressure in the cage is near a set air pressure level.

19. The method of claim 18 wherein the speeds of the two or more fans are controlled to be different by approximately 100 RPMs.

20. A method for adjusting airflow in a rodent containment cage to a set level, which comprises:

ventilating the rodent containment cage with a blower assembly connected to the rodent containment cage;

sensing air pressure with an air pressure sensor disposed in the rodent containment cage, wherein the sensor sends an air pressure signal directly to a controller;

comparing the sensed air pressure to a set level of air pressure by the controller; and

increasing or decreasing the speed of one or more fans in the blower assembly until the air pressure reaches the set level, wherein the controller slows the response rate for increasing or decreasing the speed of the one or more fans when the air pressure signal sent by the sensor to the controller is near the set level.