Sensor system for measuring and monitoring indoor air quality
View Patent ↗An apparatus for accurately sensing room conditions and positioned in the air stream to the return air plenum. The apparatus is a combination of a temperature and volatile organic compound (VOC) sensor. The sensor module is built into a ceiling grid system with the body of the sensor module extending into the return air plenum. The ceiling grid has a slot fabricated into its face which allows the air stream from the room to flow by the sensors on its way to the plenum. This enables both the temperature and the composition of the air to be monitored at the optimal location. A portable pollution sensor device that measures and monitors leading indicators of indoor air quality and the extent of pollution is used in conjunction with the ceiling grid mounted sensor modules. The portable device documents and benchmarks air quality both in buildings under construction and in existing buildings. The portable device is network-enabled so as to simultaneously transmit the data to various control devices. In addition to its use to monitor areas not otherwise covered by the ceiling grid mounted sensors, the hand-held sensor can be used during building construction to determine the best locations in the ceiling grid system for mounting of the fixed pollution sensors.
1. A ceiling system for monitoring indoor air quality, the system comprising:
a grid member having a vertical web portion and a flange portion arranged substantially perpendicular to the vertical web portion, the flange portion having a slot for allowing air to pass through the grid member; and
a sensor module mounted to the grid member, the sensor module having a housing which includes an inlet port positioned adjacent the slot of the flange portion, the sensor module having a plurality of sensors contained within the housing,
wherein each sensor monitors a specific characteristic of an air sample received through the inlet port of the housing.
2. The ceiling system of claim 1 wherein the plurality of sensors comprise a temperature sensor and a volatile organic compound (VOC) sensor.
3. The ceiling system of claim 2 further comprising a signal conditioner for amplifying an analog output signal from both the temperature sensor and the VOC sensor.
4. The ceiling system of claim 3 further comprising an analog to digital converter to convert the conditioned analog output signals to digital signals.
5. The ceiling system of claim 1 wherein the housing comprises a front cover and a rear cover, wherein the front cover and rear cover each include a slot which enables an air sample to exit the housing.
6. A sensor system for monitoring indoor air quality, comprising:
a hand-held sensor device having a housing, the housing includes an air inlet port and a plurality of sensors, the plurality of sensors being contained in the housing and wherein each sensor monitors a specific characteristic of an air sample received through the air inlet port of the housing; and
a microprocessor which evaluates the air sample and sends an output signal to a building energy management system for controlling a temperature and a mix of indoor air with fresh outdoor air, the microprocessor being wirelessly connected to the sensor device.
7. The sensor system of claim 6 wherein the plurality of sensors comprise a temperature sensor and a volatile organic compound (VOC) sensor.
8. The sensor system of claim 7 further comprising a signal conditioner for amplifying an analog output signal from both the temperature sensor and the VOC sensor.
9. The sensor system of claim 8 further comprising an analog to digital converter to convert the conditioned analog output signals to digital signals.
10. The sensor system of claim 9 wherein the microprocessor receives and processes the digital signals from the analog to digital converter.
11. The sensor system of claim 6 wherein the microprocessor determines a temperature and a composition of the air sample.
12. The sensor system of claim 6 wherein the building energy management system is a heating, ventilating and air conditioning (HVAC) system.
13. The sensor system of claim 6 wherein the building energy management system is a variable air volume (VAV) system.
14. The sensor system of claim 6 wherein the output signal is transmitted to the building energy management system by a wireless connection.
15. The sensor system of claim 14 wherein the output signal is transmitted by a radio frequency (RF) module.
16. The sensor system of claim 14 wherein the output signal is transmitted by an infrared module.
17. The sensor of claim 6 wherein the output signal is transmitted to the building energy management system by a wired connection.
18. The sensor system of claim 6 further comprising a plurality of slots in the housing to enable the air sample to exit from the housing.
19. The sensor system of claim 6 further comprising a memory module for storing a plurality of sensor data for subsequent downloading to a computer device or network.
20. The sensor system of claim 6 further comprising a light emitting diode to provide a visual indication of indoor air quality in response to an air quality status signal from the microprocessor following evaluation of the air samples.
21. The sensor system of claim 20 wherein the light emitting diode is a three-state diode, with each state corresponding to a specific status of indoor air quality.
22. A method for providing demand-controlled ventilation in an enclosed space in a building, comprising the steps of:
determining a location in a ceiling grid for mounting a multi-sensor module;
fabricating a slot in a lower surface of the ceiling grid at the determined location;
mounting the multi-sensor module to a web of the ceiling grid at the determined location, the multi-sensor module having an air inlet port, the air inlet port being positioned adjacent the fabricated slot;
sampling an air flow stream from below the multi-sensor module which passes through the fabricated slot and air inlet port of the multi-sensor module; and
evaluating the air flow stream sampled by the multi-sensor module to determine the characteristics; and
transmitting from the multi-sensor module an output signal representative of the determined characteristics of the air flow stream to a building energy management system to control the temperature and mix of air in the enclosed space.
23. The method of claim 22 wherein each sensor in the multi-sensor module monitors a different characteristic of the air flow stream sampled.
24. The method of claim 22 wherein the multi-sensor module includes a temperature sensor and a volatile organic compound (VOC) sensor.
25. The method of claim 24 further comprising the step of amplifying an analog signal output from both the temperature sensor and the VOC sensor.
26. The method of claim 22 further comprising the step of determining a temperature and composition of the air flow stream sampled by each multi-sensor module.