Patent Publication Number: US-10777064-B2

Title: Lighting with air quality and hazard monitoring

Description:
CROSS REFERENCE TO RELATED APPLICATIONS 
     The present application claims priority and is a continuation of U.S. Nonprovisional patent application Ser. No. 15/603,225, filed May 23, 2017, and titled “Lighting With Air Quality And Hazard Monitoring,” which claims priority under 35 U.S.C. Section 119(e) to U.S. Provisional Patent Application No. 62/340,969, filed May 24, 2016, and titled “Lighting With Hazard Detection And Notification,” and to Provisional Patent Application No. 62/353,489, filed Jun. 22, 2016, and titled “Lighting With Air Quality Monitoring,” the entire contents of which are incorporated herein by reference. 
    
    
     TECHNICAL FIELD 
     The present disclosure relates generally to lighting solutions, and more particularly to lighting with air quality monitoring, hazard detection, and notification functionalities. 
     BACKGROUND 
     Indoor air quality is a significant factor in occupant&#39;s health, productivity, comfort, and overall satisfaction with a building structure. In a commercial space, indoor air quality can have significant economic implications for occupants and landlords. In some cases, indoor air pollutant levels may be significantly higher than outdoor air pollutant levels. In addition to pollutants that enter an indoor space from outside, contaminants such as volatile organic compounds may be released by cleaning materials, building materials, and even furniture. ASHRAE and other sustainability codes and standards specify specific metrics and standards around ventilation rates, moisture, contaminants/pollutants, temperature, and many other factors. 
     Air quality sensors may be used to monitor the air quality of an indoor space. Further, many safety hazards such as fire, carbon monoxide, natural gas, and earthquake can be detected by specialized sensors. The quality of data collected from indoor air quality sensors and the effectiveness of safety hazard sensors may be dependent on the number of distributed sensors. 
     While some sensors operate on battery power, other sensors may require electrical wiring to receive power from the mains power supply. In some cases, adding wiring to existing structures may be particularly challenging. Further, conflicting priorities may exist between preferred locations for sensors that detect air quality and safety hazards and preferred locations for providing notification of detected air quality and detected safety hazards, for example, to occupants of a building. Thus, a solution that allows effective distribution of indoor air quality sensors and safety hazard sensors and that provides flexibility in installing the sensors while enabling improved notification of air quality and safety hazards is desirable. 
     SUMMARY 
     The present disclosure relates generally to lighting solutions, and more particularly to lighting with air quality monitoring, hazard detection, and notification functionalities. In an example embodiment, a sensing and lighting device includes a lighting fixture comprising a light emitting diode (LED) light source. The sensing and lighting device further includes a sensor to sense the air at the sensor, and a power source. The LED light source and the sensor are powered by the power source. 
     In another example embodiment, a sensing and lighting device includes a lighting fixture comprising a light emitting diode (LED) light source. The sensing and lighting device further includes a sensor to sense the air at the sensor and a driver that provides power to the LED light source. The sensing and lighting device also includes a control device that controls the power provided by the driver to the LED light source based on whether a hazard condition is detected by the sensor. 
     In another example embodiment, a system of sensing and lighting devices includes a first sensing and lighting device, a second sensing and lighting device, and a wireless control device that wirelessly receives air quality information from the first sensing and lighting device and from the second sensing and lighting device. The first sensing and lighting device and the second sensing and lighting device each includes a lighting fixture comprising a light emitting diode (LED) light source. The first sensing and lighting device and the second sensing and lighting device each further includes a sensor to sense the air at the sensor and a power source, where the LED light source and the sensor are powered by the power source. 
     These and other aspects, objects, features, and embodiments will be apparent from the following description and the appended claims. 
    
    
     
       BRIEF DESCRIPTION OF THE FIGURES 
       Reference will now be made to the accompanying drawings, which are not necessarily drawn to scale, and wherein: 
         FIG. 1  illustrates a sensing and lighting device with an integrated sensor according to an example embodiment; 
         FIG. 2  illustrates a sensing and lighting device according to another example embodiment; 
         FIG. 3  illustrates a sensing and lighting device according to another example embodiment; 
         FIG. 4A  illustrates the sensing and lighting device of  FIG. 3  including the control device according to another example embodiment; 
         FIG. 4B  illustrates an example circuit schematic of the 0-10 v circuit of the control device shown in  FIG. 4A ; 
         FIG. 5  illustrates a sensing and lighting device according to another example embodiment; 
         FIG. 6  illustrates the control device of the sensing and lighting device of  FIG. 5  according to an example embodiment; 
         FIG. 7  illustrates a method of air quality monitoring, hazard detection, and notification using the sensing and lighting devices of  FIGS. 1, 2, 3, and 5  according to an example embodiment; 
         FIG. 8  illustrates a method of hazard detection and notification using the hazard detection and notification lighting device of  FIGS. 1, 3, and 5  according to another example embodiment; 
         FIG. 9  illustrates a method of hazard detection and notification using the hazard detection and notification lighting device of  FIGS. 1, 3, and 5  according to another example embodiment; 
         FIG. 10  illustrates the sensing and lighting device of  FIG. 1  installed in a ceiling according to an example embodiment; 
         FIG. 11  illustrates the sensing and lighting device of  FIG. 2  installed in a ceiling according to an example embodiment; 
         FIG. 12  illustrates the sensing and lighting device of  FIG. 2  installed in a ceiling according to another example embodiment; and 
         FIG. 13  illustrates a network of the sensing and lighting devices according to an example embodiment. 
     
    
    
     The drawings illustrate only example embodiments and are therefore not to be considered limiting in scope. The elements and features shown in the drawings are not necessarily to scale, emphasis instead being placed upon clearly illustrating the principles of the example embodiments. Additionally, certain dimensions or placements may be exaggerated to help visually convey such principles. In the drawings, reference numerals designate like or corresponding, but not necessarily identical, elements. 
     DETAILED DESCRIPTION OF THE EXAMPLE EMBODIMENTS 
     In the following paragraphs, example embodiments will be described in further detail with reference to the figures. In the description, well known components, methods, and/or processing techniques are omitted or briefly described. Furthermore, reference to various feature(s) of the embodiments is not to suggest that all embodiments must include the referenced feature(s). 
     Light fixtures are often widely distributed through a room or a building and may be continuously powered for long time durations. In many applications, light fixtures may also be integral parts of the air ventilation system of a building, where air return venting is contained within the light fixtures themselves. By leveraging the physical infrastructure of light fixtures, such as electrical wirings and support structures, sensor(s) that monitor air quality and/or that detect hazards may be integrated with light fixtures and operate in a seamless manner. For example, a sensor can be physically and electrically connected to a light fixture and leverage the communication network used by the light fixture. In some applications, a sensor that is integrated with lighting fixtures may communicate with a remote control device and/or with each other on a communication network that is separate from the communication network used by the lighting fixtures. The light sources of light fixtures may also be used to provide visual notifications upon detections of hazard conditions including low air quality conditions. Thus, lighting devices that have integrated sensor(s) may be used for illumination as well as for air quality monitoring, hazard detection, and notification of hazards including low air quality issues. 
     Turning now to the figures, particular example embodiments are described.  FIG. 1  illustrates a sensing and lighting device  100  with an integrated sensor according to an example embodiment. Referring to  FIG. 1 , in some example embodiments, the sensing and lighting device  100  includes a lighting fixture  102  and a sensor  104 . For example, the sensor  104  may be an air quality sensor, a hazard sensor, such as a fire sensor, a smoke sensor, a carbon monoxide sensor, an earth quake sensor, a natural gas sensor, and/or another type of sensor that can be integrated with the lighting fixture  102  as described herein. The sensing and lighting device  100  may also include a power source device  106  that provides power to the lighting fixture  102  and to the sensor  104 . The lighting fixture  102  includes a housing  110  having a cavity  122 . The lighting fixture  102  also includes a light source  108 , such as an LED light source, that is powered by the power source device  106 . For example, the light source  108  may be at least partially positioned in the housing  110 . 
     In some example embodiments, the power source device  106  may be coupled to an AC power supply such as a mains supply via a connection  118  (e.g., electrical wires). For example, the power source device  106  may include one or more AC/DC converters to generate and provide DC power to the light source  108  and to the sensor  104 . For example, the power source device  106  may provide DC power to the light source  108  and to the sensor  104  at different voltage levels. 
     In some example embodiments, the power source device  106  may include a driver, such as an LED driver, that provides power to the light source  108  via a connection  114  (e.g., one or more electrical wires). The power source device  106  may also include another power supply that provides DC power to the sensor  104  via a connection  116  (e.g., one or more electrical wires). 
     In some example embodiments, the housing  110  of the lighting fixture  100  may have a lower opening  112  and an upper opening  120 . To illustrate, the lower opening  112  and the upper opening  120  may allow air to flow through the cavity  122  of the housing  110 . The sensor  104  may be positioned such that air flowing through the cavity  122  of the housing  110  passes by the sensor  104 . For example, the sensing and lighting device  100  is sized to fit in an air duct (e.g., an return air duct or plenum) of air conditioning system such as an HVAC (heating, ventilation, and air conditioning) system. The sensor  104  may monitor, for example, one or more of carbon monoxide level, carbon dioxide level, humidity, volatile organic compound(s), airborne particles above a particular size, temperature, natural gas, and/or other elements that allow the sensor  104  to monitor air quality and/or detect fire, smoke, etc. 
     In some example embodiments, the power source device  106  may include a wireless transmitter and receiver to wirelessly communicate with a remote control/monitoring device (e.g., a lighting control device), with other lighting fixtures, and/or with other sensing and lighting devices. For example, the sensor  104  may transmit sensor data such as air quality information (e.g., the presence or amount of an air pollutant) and hazard conditions (e.g., fire, smoke, low air quality such as when the amount of a pollutant exceeds a threshold, etc.) using the wireless transmitter that is in the power source device  106 . Alternatively, the sensor  104  may transmit the sensor data over a wireless network that is different from of the lighting control wireless network used by the lighting fixture  102 . The sensor  104  may alternatively or in addition transmit the sensor data over a wired connection directly or through the power source device  106 . In some example embodiments, the sensing and lighting device  100  may not communicate wirelessly for lighting control purposes. 
     In some example embodiments, the light source  108  may flash its light to indicate detection of a hazard condition. For example, the device  100  may flash the light emitted by the light source  108  to indicate when a level of one or more of carbon monoxide, carbon dioxide, etc. exceeds a threshold level. As another example, the device  100  may flash the light emitted by the light source  108  to indicate detection of fire, smoke, earthquake, etc. Alternatively or in addition, the sensing and lighting device  100  may generate an audible notification of hazard conditions. 
     Although one sensor  104  is shown, in some alternative embodiments, the sensing and lighting device  100  may include two or more sensors of the same type or different types. For example, the sensing and lighting device  100  may include multiple sensors that sense different elements/conditions (e.g., carbon monoxide level, concentration of airborne particles, etc.) in the air that flow past the sensors. As another example, one or more sensors may monitor air quality and another one or more sensors may detect hazard conditions such as earthquakes. In some alternative embodiments, the sensor  104  may be positioned at a different location than shown in  FIG. 1  without departing from the scope of this disclosure. For example, the sensor  104  may be positioned entirely within the cavity  122  of the housing  110 , on a top cover of the housing  110 , where the top cover has one or more openings such as the opening  120  to allow air to flow through the cavity  122  past the sensor  104 . 
       FIG. 2  illustrates a sensing and lighting device  200  according to another example embodiment. In some example embodiments, the sensing and lighting device  200  includes a lighting fixture  202  and the sensor  104  described above. The sensing and lighting device  200  may also include the power source device  106  that provides power to the lighting fixture  202  and to the sensor  104  in the same manner as described above with respect to the sensing and lighting device  100 . 
     In some example embodiments, the lighting fixture  202  includes a housing  204  and the light source  108 . For example, the power source device  106  may be positioned on a top cover  206  of the housing  204  and may provide power to the light source  108  as described above with respect to  FIG. 1 . To illustrate, the power source device  106  may provide power to the light source  108  via the connection  114  and may provide power to the sensor  104  via the connection  116 . 
     In contrast to the sensor  104  of the device  100  of  FIG. 1 , in the sensing and lighting device  200 , the sensor  104  is positioned on the outside of the housing  204 . For example, the sensor  104  may monitor the air flowing past the sensor  104  on the outside of the housing  204  instead of the air flowing through the housing  204 . To illustrate, the housing  204  may include the lower opening  208  but may be substantially covered by the top cover  206  that limits air flow through the housing  204 . The lighting device  200  may be sized to fit in an HVAC air duct (e.g., an air return duct) of an HVAC system of a room or a building. 
     In some example embodiments, the light source  108  may flash its light to indicate detection of hazard conditions. For example, the light emitted by the light source  108  may flash to indicate levels of carbon monoxide, carbon dioxide, etc. that exceed threshold levels. As another example, the light emitted by the light source  108  may flash to indicate detection of fire, smoke, earthquake, etc. Alternatively or in addition, the sensing and lighting device  100  may generate an audible notification of low air quality conditions (e.g., detection of a particular pollutant or excessive amount of a pollutant) and other hazard conditions (e.g., fire, smoke, etc.). 
     In some alternative embodiments, the sensor  104  may be positioned at a different location than shown in  FIG. 2  without departing from the scope of this disclosure. Although one sensor  104  is shown in  FIG. 2 , in some alternative embodiments, the sensing and lighting device  200  may include two or more sensors that monitor and/or detect different elements/conditions such as fire, smoke, various airborne particles, etc. 
       FIG. 3  illustrates a sensing and lighting device  300  according to another example embodiment. In some example embodiments, the sensing and lighting device  300  includes a lighting fixture  302  that includes the light source  108 , a driver  306 , a control device  310 , and the sensor  104 . The sensing and lighting device  100  may also include a siren  314 . The light source  108  of the lighting fixture  302  may be an LED light source, and the driver  306  may be an LED driver (e.g., a 0-10 v dimmable LED driver). The driver  306  may be coupled to the light source  108  to provide power to the light source  108 . For example, the driver  306  may generate and provide DC power to the light source  108  based on an input AC power from the controller device  410  as described below. The light source  108  may be located inside a housing  308  of the lighting fixture  302 , and the driver  306  may be outside the housing  308 . For example, the driver  306  and the control device  310  may be included in the power source device  106  described with respect to  FIGS. 1 and 2 . Alternatively, the driver  306  may be integrated with the light source  108  or may otherwise be located inside the housing  308 . 
     In some example embodiments, the control device  310  is connected to the sensor  104  via the electrical connection  116 . As described above, the sensor  104  may be one of different types of sensors such as a fire sensor, a smoke sensor, a carbon monoxide sensor, an earth quake sensor, a natural gas sensor, and/or another sensor that may be integrated with the lighting fixture  302 . To illustrate, the sensor  104  may monitor, for example, one or more of carbon monoxide level, carbon dioxide level, humidity, volatile organic compound(s), airborne particles above a particular size, temperature, natural gas, and/or other elements that allow the sensor  104  to monitor air quality and/or detect fire, smoke, etc. 
     In some example embodiments, the control device  310  is also coupled to the driver  306  via an electrical connection such as electrical wires/traces and/or connectors. For example, the control device  310  may provide dim control and/or other lighting control signal(s) to the driver  306 . To illustrate, the driver  306  may change the dim level of the light emitted by the light source  108  based on the dim control signal provided by the control device  310 . 
     In some example embodiments, AC power may also be provided to the driver  306  from the control device  310  via an electrical connection. To illustrate, AC power may be provided to the control device  310  via the electrical connection  118 , and the control device  310  may provide a switched AC power to the driver  306 . For example, the control device  310  may include a relay that provides the switched AC power to the driver  306 . The control device  310  may turn on/off the switched AC power provided to the driver  306  by switching on/off the relay. In some alternative embodiments, the line AC power that is not a switched-power may be provided to the driver  306  through the control device  310  or outside the control device  310 . In some alternative embodiments, DC power instead of AC power may be provided to the control device  310  via the connection  118 . In some example embodiments, the connection  118  may be an Ethernet cable (e.g., CAT 5e) that is used to provide power as well as for wired communication. 
     In some example embodiments, the sensor  104  may receive power from the driver  306 . Alternatively, in some example embodiments, the sensor  104  may receive power from the control device  310 . For example, the control device  306  may include a power supply (e.g., a battery, an AC/DC converter, etc.) that provides the appropriate power level to the sensor  104  via the electrical connection  116 . 
     In some example embodiments, the control device  310  may receive one or more sensor signals from the sensor  104  that provide, for example, air quality information and hazard condition that have been detected by the sensor  104 . For example, the sensor  104  may provide the information to the control device  310  via the connection  116 , which may include multiple electrical wires. When the sensor  104  indicates a detection of a hazard condition to the control device  310 , the control device  310  may cause the light emitted by the light source  108  to flash to provide a visual notification of the detection of the hazard condition. For example, the control device  310  may repeatedly change dim levels indicated by the dim control signal provided to the driver  306  between relatively high and relatively low intensity levels to cause the light emitted by the light source  108  to flash. 
     In some alternative embodiments, instead of using the dim control signal, the control device  310  may continually turn on and off the switched AC power provided to driver  306  by switching the relay of the control device  310  on/off. The turning on and off of the switched AC power results in the driver  306  turning on/off the power that the driver  306  provides to the light source  108 , resulting in the flashing of the light emitted by the light source  108 . 
     In some example embodiments, the siren  314  may generate an audible notification of one or more conditions including detected hazard conditions such as fire, smoke, low air quality, etc. For example, the siren  314  may be coupled to the control device  310  such that the control device  310  turns on the siren  314  to provide the audible notification upon detection of a hazard condition by the sensor  104  and/or to provide other notifications, for example, related to low air quality based on air quality monitoring by the sensor  104 . The control device  310  may turn on the siren  314  by switching the power provided to the siren  314  over the electrical connection  316  (e.g., one or more electrical wires) or by providing an electrical signal that turns on to the siren  314  over the electrical connection  316 . 
     In some example embodiments, the light source  108  may flash its light at a particular rate (e.g., flashing) to indicate a path, for example, to an exit door. For example, multiple lighting devices  300  that are disposed along a path that leads to an exit door may flash at a faster rate than other lighting devices  100  that are not along the path to the exit door. In some example embodiments, the path may be from an entrance to a possible cause of a hazard condition detected by the sensing and lighting device  300 . For example, the particular sensing and lighting device  300  that detects a hazard condition may indicate (e.g., via wireless communication) the detection of a hazard to other instances of the lighting devices  300  either directly or via a centralized controller. 
     Some instances of the lighting devices  300  that are in the path from an entrance to the particular sensing and lighting device  300  that detected the hazard may flash their lights at a rate that is different from other lighting devices  300  that are not in the path. For example, location information of multiple lighting devices  300  may be stored in each individual sensing and lighting device  300  or in a central controller, for example, during system provisioning, and the location information may be used to identify the lighting devices  300  that are in a path to/from an exit/entrance. In some alternative embodiments, the sensing and lighting device  300  may include one or more indicator light sources (e.g., an LED light source that emits a particular color (e.g., red) light), where the indicator light sources are turned on if the sensing and lighting device  300  is in a path, for example, to/from an exit/entrance or to the particular sensing and lighting device  300  that detected the hazard condition. 
     Although one sensor is shown in  FIG. 3 , in some alternative embodiments, the sensing and lighting device  300  may include more sensors without departing from the scope of this disclosure. In some alternative embodiments, the components of the sensing and lighting device  100  including the sensor  104 , the driver  306 , the control device  310 , and the siren  314  may be located differently than shown without departing from the scope of this disclosure. In some alternative embodiments, some of the components (e.g., the driver  306  and the control device  310 ) may be integrated into a single device such as the power source device  106  shown in  FIGS. 1 and 2 . In some alternative embodiments, another type of sound generation device may be used instead of or in addition to the siren  314  without departing from the scope of this disclosure. In some alternative embodiments, the sensor  104  that is shown on the outside of the housing  308  may be positioned inside the housing  308 , for example, in a similar manner as shown in  FIG. 1 . In some alternative embodiments, the housing  308  may include one or more upper openings to allow air flow through the housing  308 . 
       FIG. 4A  illustrates the sensing and lighting device  300  of  FIG. 3  including the control device  310  according to another example embodiment. Referring to  FIGS. 3 and 4A , the control device  310  includes a controller  402  such as a microcontroller. The control device  310  may also include a wireless transceiver  404 , a power supply  406 , a 0-10 v dim control circuit  408 , and relay  410 . The controller  402  is in electrical communication with the transceiver  404 , the 0-10 v circuit  408 , and the relay  410 . The controller  402  is also in electrical communication with the sensor  104  and the optional siren  314 . For example, the controller  402  may be an integrated circuit controller such as PIC16F690. In some alternative embodiments, the controller  402  may be implemented using multiple circuits and components using an FPGA, an ASIC, or a combination thereof. The controller  402  may also include one or more memory devices for storing code that may be executed by the controller  402  and for storing data. 
     In some example embodiments, the power supply  406  may be coupled to a mains power via an input power line (Line), and may generate DC power provided to the controller  402 , the transceiver  404 , the 0-10 v circuit  408 , the sensor  104 , and the siren  314 . As a non-limiting example, the power supply  406  may provide approximately 3.3V to the controller  402  and to the transceiver  404 , and approximately 16V to the 0-10 v circuit  408 , the sensor  104 , and the siren  314 . In some alternative embodiments, the power supply  406  may provide other voltage levels to the controller  402 , the transceiver  404 , the 0-10 v circuit  408 , the sensor  104 , and the siren  314  without departing from the scope of this disclosure. Alternatively, the sensor  104  may be powered by the driver  306  instead of by the power supply  406  without departing from the scope of this disclosure. In some alternative embodiments, DC power instead of AC power may be provided to the power supply  406 , and the power supply  406  may generate different DC power outputs, for example, using DC/DC converter circuits. 
     In some example embodiments, the transceiver  404  may wirelessly receive lighting control commands and pass the commands to the controller  402  for processing. For example, based on the received commands, the controller  402  can switch on/off the relay  410 , which is coupled to the AC power source by the connection  118  via the input power line (Line), to turn on/off the switched AC power signal provided by the relay  410  on an output power line (Switched Line). For example, the Switched Line may be coupled to the driver  306  shown in  FIG. 3 , and the switched AC power signal from the relay  410  may be provided to the driver  306  via the Switched Line. 
     In some example embodiments, based on commands wirelessly received by the transceiver  404 , the controller  402  may also control the 0-10 v circuit  408  to change the dim control signal provided by the 0-10 v circuit  408  via an output 0-10 v port  414 . For example, the controller  402  may provide a pulse-width-modulation (PWM) signal or another output signal to the 0-10 v circuit  408  via a connection  412  (e.g., one or more electrical wires or traces), and the 0-10 v circuit  408  may generate the dim control output signal that is provided on the 0-10 v output port  414 , for example, to the driver  306 . 
       FIG. 4B  illustrates an example circuit schematic of the 0-10 v circuit  408  of the control device  310  shown in  FIG. 4A . Referring to  FIGS. 3, 4A, and 4B , in some example embodiments, the controller  402  may provide an output control signal to the 0-10 v circuit  408  via the connection  412 , and the 0-10 v circuit  408  may generate the corresponding dim control output signal on the output 0-10 v port  414  to control the amount of power that the driver  306  provides to the light source  108 . Although particular parameter values are shown in  FIG. 4B , in some alternative embodiments, other parameter values may be used without departing from the scope of this disclosure. Further, the 0-10 v circuit  408  may include other components and circuitry than shown in  FIG. 4B  without departing from the scope of this disclosure. 
     In some example embodiments, the transceiver  404  may wirelessly transmit lighting-related information, such as lighting status information. For example, the controller  402  may receive status and other lighting related information from the driver  306  and provide the information (as received and/or processed) to the transceiver  404  for wireless transmission. 
     In some example embodiments, the transceiver  404  may wirelessly transmit sensor-related information in addition or instead of lighting-related information. For example, the controller  402  may receive sensor-related information (e.g., air quality information, hazard condition information, etc.) from the sensor  104  and provide the information (as received and/or processed) to the transceiver  404  for wireless transmission. For example, the transceiver  404  may transmit the sensor-related information to a remote monitoring/control device such as to mobile wireless device that may have a resident software application, for example, to process, display, transmit the information received from the transceiver  404 . The transceiver  404  may also wirelessly receive information (e.g., instructions) intended for the sensor  104 . 
     In some example embodiments, the sensor  104  may provide one or more sensor signals to the controller  402  to indicate whether the sensor  104  is detecting/has detected a hazard condition, such as a gas leak, a low air quality condition, or other relevant conditions that may require providing a notification. To illustrate, when a sensor signal from the sensor  104  indicates the detection of a hazard condition such as a gas leak, fire, smoke, low air quality, etc., the controller  402 , in response to the detection, may repeatedly switch on/off the relay  410  to turn on/off the switched AC power from the relay  410 . The driver  306 , which receives the switched AC power, may correspondingly turn on/off the DC power that the driver  306  provides to the light source  108  based on the switched AC power. The repeated turning on/off the DC power causes the flashing of the light emitted by the light source  108 , which can serve as a visual notification of the detection of the hazard condition by the sensor  104 . When the indicator signal from the sensor  104  stops indicating to the controller  402  the detection of the hazard condition, the controller  402  may return the relay  410  to the pre-hazard detection state or another default state, or otherwise return the relay  410  to a normal operating state. Visual notification may be provided using the light emitted by the light source  108  in a similar manner for other conditions that require notification in response to detection by the sensor  104 . 
     In some alternative embodiments, in response to the sensor  104  indicating the detection of the hazard condition to the controller  402 , the controller  402  may control the 0-10 v circuit  408  to change the dim level of the light emitted by the light source  108 . For example, the controller  402  may repeatedly change the output control signal that the controller  402  provides to the 0-10 v circuit  408 , and, in response, the 0-10 v circuit  408  may repeatedly change the dim control signal at the 0-10 v output port  414  to corresponding to different dim levels (e.g., between 10% and 90% dim levels). The driver  306 , which may be coupled to the 0-10 v output port  414 , may correspondingly change the power provided to the light source  108  to repeatedly change the dim levels of the light emitted by the light source  108 . When the indicator signal from the sensor  104  stops indicating to the controller  402  the detection of the hazard condition, the controller  402  may control the 0-10 v circuit  408  to change the dim level of the emitted light to a pre-hazard detection state or to another default state, or otherwise return the 0-10 v circuit  408  to a normal operating state. Visual notification may be provided using the light emitted by the light source  108  in a similar manner for other conditions that require notification in response to detection by the sensor  104 . 
     In some example embodiments, the controller  402  may turn on the siren  314  to provide an audio notification of the detection of a hazard condition (e.g., fire, low air quality, etc.) and/or other similar conditions monitored and/or detected by the sensor  104 . The controller  402  may turn off the siren  314  when the sensor signal(s) from the sensor  104  stops indicating the detection of the particular hazard or other condition to the controller  402 . 
     In some alternative embodiments, the driver  306  may include a transceiver that is used for wireless communication instead of or in addition to the transceiver  404 . For example, a transceiver in the driver  306  may operate in a similar manner as described above to receive and transmit lighting-related information and/or sensor-related information. 
     In some example embodiments, the sensor  104  may provide to the controller  402  one or more information signals that provide information such as temperature, airborne particles, etc. instead of or in addition to providing sensor signal(s) that indicates a hazard condition such as a gas leak, fire, smoke, low air quality, etc. to the controller  402 . The controller  402  may process the information signal(s) and determine whether to provide a notification of a hazard condition, for example, based on threshold levels stored in a memory device of the control device  310 . Upon determining that a notification should be issued, the controller  402  may cause the light source  108  to flash its light or to otherwise provide other visual notification, turn on the siren  314 , and/or wirelessly transmit a notification via the transceiver  404 . Upon determining that the condition that resulted in the notification is no longer present, for example, based on the information signal(s) from the sensor  104 , the controller  402  may return the control device  310  to a pre-hazard notification state or to an otherwise normal operating state. For example, the controller  402  may stop the light source  108  and the siren  314  from providing visual and audio notification. The controller  402  may also wirelessly transmit information to a remote monitoring/control device to indicate that the hazard condition no longer exists. 
     Although particular components and connections are shown in  FIGS. 4A and 4B , in alternative embodiments, the control device  310  may include other components and connection instead of or in addition to those shown. In some alternative embodiments, some of the components shown in  FIGS. 4A and 4B  may be integrated into a single component without departing from the scope of this disclosure. In some alternative embodiments, some of the components shown in  FIGS. 4A and 4B  may be omitted without departing from the scope of this disclosure. For example, the relay  410  may be omitted and AC power may be provided to the driver  306  without being controlled by the relay  410 . In some alternative embodiments, DC power instead of AC power may be provided to the power supply  406  that generates via the connection  118 . 
       FIG. 5  illustrates a sensing and lighting device  500  according to another example embodiment. The lighting device  500  is substantially the same as the sensing and lighting device  300  of  FIG. 3 . For example, the lighting device  500  may include the lighting fixture  302  that includes the light source  108  and the driver  306  that is electrically coupled to the light source  108  to provide DC power to the light source  108 . In contrast to the sensing and lighting device  300  where the driver  306  is shown as receiving AC power from the control device  310 , the driver  306  in the sensing and lighting device  500  may receive AC power from a mains power supply provided via the connection  118  and may generate and provide DC power to the light source  108  from the AC power. In some alternative embodiments, DC power instead of AC power may be provided to the driver  306  via the connection  118 . In some alternative embodiments, the driver  306  may be integrated with the light source  108 , or may otherwise be located inside the housing  308 . 
     In some example embodiments, the sensing and lighting device  500  includes a control device  502 , the sensor  104 , and the siren  314 . The control device  502  is connected to the sensor  104  and the siren  314  in the same manner as described with respect the control device  310  of  FIG. 3 . The control device  502  also controls the driver  306  in a similar manner as described with respect to  FIG. 3 , for example, to change the dim level of the light emitted by the light source  108 . 
     In some example embodiments, in contrast to the control device  310  of  FIG. 3 , the control device  502  may include or may be coupled to a battery power source. For example, the control device  502  may provide DC power to the sensor  104  and the siren  314  directly from a battery or by generating DC power, for example, using one or more DC/DC converter that convert DC power from the battery to power levels compatible with the sensor  104  and the siren  314  as well as other components. 
     In some example embodiments, the sensing and lighting device  500  performs air quality monitoring, hazard detection, and notification in the same manner as described above with respect to the sensing and lighting device  300 . 
       FIG. 6  illustrates the control device  502  of the sensing and lighting device  500  of  FIG. 5  according to an example embodiment. Referring to  FIGS. 3-6 , the control device  502  includes the controller  402 , the wireless transceiver  404 , the 0-10 v dim control circuit  408 , and a power supply  602 . The controller  402  is in electrical communication with the transceiver  404  and the 0-10 v circuit  408  and operates in a same manner as described above. The controller  402  is also in electrical communication with the sensor  104  and the siren  314  in the same manner as described above. 
     In contrast to the power supply  406  of the control device  310 , the power supply  602  includes a battery  604  as a power source instead of the mains supply. To illustrate, the power supply  406  may generate from the battery  604  DC power that is provided to the controller  402 , the transceiver  404 , the 0-10 v circuit  408 , the sensor  104 , and the siren  314 . For example, the power supply  402  may include one or more DC/DC converters to generate the appropriate DC levels. As a non-limiting example, the battery  604  may be a 9-Volt battery that is used to generate approximately 3.3V and 16V using DC/DC converters in a manner known to those of ordinary skill in the art with the benefit of this disclosure. In some alternative embodiments, DC power may be provided to one or more components of the sensing and lighting device  500  from the battery  604  instead of from a DC/DC converter. 
     In some example embodiments, in response to one or more signals from the sensor  104 , the controller  402  may control the 0-10 v circuit  408  to flash the light emitted by the light source  108 , to change the intensity level of the light, etc. in the same manner as described above. 
     Although the battery  604  is shown inside the power supply  602 , in alternative embodiments, the battery  604  may be outside of the power supply  602  or outside of the control device  502 . Although particular components and connections are shown in  FIG. 6 , in alternative embodiments, the control device  502  may include other components and connection instead of or in addition to those shown. In some alternative embodiments, some of the components shown in  FIG. 6  may be integrated into a single component without departing from the scope of this disclosure. In some alternative embodiments, some of the components shown in  FIG. 6  may be omitted without departing from the scope of this disclosure. 
       FIG. 7  illustrates a method  700  of air quality monitoring, hazard detection, and notification using the sensing and lighting devices of  FIGS. 1, 2, 3, and 5  according to an example embodiment. Referring to  FIGS. 1-7 , the method  700  includes determining whether a sensor event is triggered, at step  702 . For example, the sensor  104  may provide to the controller  402  a signal indicating the detection of smoke, fire, carbon monoxide, natural gas leak, earth quake or another hazardous condition such as low air quality. Alternatively, the controller  402  may determine whether a hazard condition exists by comparing sensor data from the sensor  104  against a threshold level. If the hazard condition and/or a condition that otherwise requires providing a notification exist, the method  700  may include, at step  704 , turning on the siren  314 . At step  706 , the method  700  includes flashing the light emitted by the light source  108  using the 0-10 v circuit  408  or the relay  410  as described above. Alternatively, the controller  402  may control a dimming circuit other than the 0-10 v circuit  408  to flash the light emitted by the light source  108 . 
     In some example embodiments, the method  700  includes at step  708  transmitting a notification of the hazard condition. For example, the controller  402  may use the transceiver  404  to wirelessly transmit information indicating the hazard condition (e.g., fire, low air quality, etc.), for example, to a control/monitoring station. The transceiver  404  may transmit wireless signals compatible with one or more wireless standards Wi-Fi, ZigBee, Bluetooth, etc. At step  710 , the method  700  may include waiting for a period of time (e.g., 10 seconds, 30 seconds, 1 minute, etc.) before returning to step  702  to keep monitoring whether a sensor event is triggered. For example, by waiting for a period of time at step  710 , the flashing of the light emitted by the light source  108  is likely to have occurred enough times to be noticed by occupants of a room. 
     In some example embodiments, if a hazard condition or another condition that may require notification is not detected at step  702 , the method  700  includes, at steps  712 ,  714 , keeping or turning the siren  314 , if present, off, and stopping, if already flashing, the light emitted by the light source  108  from flashing. From step  714 , the method  700  continues with checking whether a sensor event is triggered at step  702 . 
     Although a particular order of the steps of the method  700  are shown in  FIG. 7 , in some alternative embodiments, some of the steps may be performed in a different order than shown or may be omitted or skipped without departing from the scope of this disclosure. Although particular steps and orders of the steps of the method  700  are shown in  FIG. 7 , in alternative embodiments, the method  700  may include other steps before, between, or after the steps described above. 
       FIG. 8  illustrates a method  800  of hazard detection and notification using the hazard detection and notification lighting device of  FIGS. 1, 3, and 5  according to another example embodiment. Referring to  FIGS. 1-6 and 8 , in some embodiments, the method  800  includes detecting a hazard condition by a sensor at step  802 . For example, the sensor  104  may detect a hazard condition such as fire, smoke, low air quality, etc. At step  804 , the method  800  may include receiving, by a controller, a hazard indicator signal from the sensor. For example, the controller  402  may receive a sensor signal from the sensor  104 , where the sensor signal indicates the detection of a hazard condition by the sensor  104  or the signal may carry information that may be used to determine whether a hazard condition exists. 
     At step  806 , the method  800  may include, in response to receiving the hazard indicator signal, changing a dim control signal provided to a driver of a lighting fixture to flash a light emitted by a light source of the lighting fixture between different dim levels. For example, the controller  404  may control the 0-10 v circuit so that the 0-10 v circuit changes a dim control signal provided to the driver  306  repeatedly such that the light emitted by the light source  108  flashes. 
     Although particular steps and orders of the steps of the method  800  are shown in  FIG. 8 , in alternative embodiments, the method  800  may include other steps before, between, or after the steps described above. 
       FIG. 9  illustrates a method  900  of hazard detection and notification using the hazard detection and notification lighting device of  FIGS. 1, 3, and 5  according to another example embodiment. Referring to  FIGS. 1-6 and 9 , in some embodiments, the method  900  includes at step  902  detecting a hazard condition by a sensor. For example, the sensor  104  may detect a hazard condition such as fire, smoke, low air quality, etc. At step  904 , the method  900  includes receiving, by a controller, a hazard indicator signal from the sensor. For example, the controller  402  may receive a sensor signal from the sensor  104 , where the sensor signal indicates the detection of a hazard condition by the sensor  104  or the signal may carry information that may be used to determine whether a hazard condition exists. 
     At step  906 , the method  900  includes, in response to receiving the hazard indicator signal, switch a relay between on and off to flash a light emitted by a light source of the lighting fixture, wherein power is provided to the light source by the relay. For example, the controller  404  may control the relay  410  to cause the light emitted by the light source to flash. 
     Although particular steps and orders of the steps of the method  900  are shown in  FIG. 9 , in alternative embodiments, the method  900  may include other steps before, between, or after the steps described above. 
       FIG. 10  illustrates the sensing and lighting device  100  of  FIG. 1  installed in a ceiling  1004  according to an example embodiment. Referring to  FIGS. 1 and 10 , in some example embodiments, the sensing and lighting device  100  is positioned in an air duct  1002  that is behind the ceiling  1004 . For example, the air duct  1002  may be an HVAC air duct, and the sensing and lighting device  100  may be positioned in an inside space  1006  of the air duct  1002  proximal to an opening of the air duct  1002 . To illustrate, the air duct  1002  may be an HVAC return air duct where air flows into the air duct  1002  from the area below the ceiling  1004  that is air conditioned by the air conditioning system. For example, the area below the ceiling  1004  may be an area that is occupied by people or that is connected to such an area. As air flows through the sensing and lighting device  100  and past the sensor  104 , the sensor  104  may monitor the quality of the air as described above with respect to  FIG. 1 . In some example embodiments, the air duct  1002  may be a supply air duct (e.g., an HVAC supply air duct). 
     Although  FIG. 10  illustrates the sensing and lighting device  100  of  FIG. 1  installed in a ceiling, in some alternative embodiments, the sensing and lighting devices  300 ,  500  may instead be installed in the ceiling, where the sensor  104  is positioned in the inside of the housing of the lighting fixture. In some alternative embodiments, the sensor  104  may be in the path of the return air at a location other than shown in  FIG. 10  without departing from the scope of this disclosure. 
       FIG. 11  illustrates the sensing and lighting device  200  of  FIG. 2  installed in a ceiling  1104  according to an example embodiment. Referring to  FIGS. 2 and 11 , the sensing and lighting device  200  is positioned in the air duct  1102  behind a ceiling  1104 . For example, the air duct  302  may be an HVAC return air duct where air flows into the air duct  1102  from the area below the ceiling  1104 . For example, the area below the ceiling  1104  may be an area that is occupied by people or that is connected to such an area. The sensing and lighting device  200  may be positioned in an inside space  1106  of the air duct  1102  proximal to an opening of the air duct  1102 . As air flows past the sensor  104  of the lighting device  200  on the outside of the lighting fixture  202 , the sensor  104  may monitor the quality of the air as described above with respect to  FIG. 2 . In some example embodiments, the air duct  1102  may be a supply air duct (e.g., an HVAC supply air duct). 
     Although  FIG. 11  illustrates the sensing and lighting device  200  of  FIG. 2  installed in a ceiling, in alternative embodiments, the sensing and lighting devices  100 ,  300 ,  500  may instead be installed in the ceiling in a similar manner. In some alternative embodiments, the sensor  104  may be in the path of the return air at a location other than shown in  FIG. 11  without departing from the scope of this disclosure. 
       FIG. 12  illustrates the sensing and lighting device  200  of  FIG. 2  installed in a ceiling  1204  according to another example embodiment. Referring to  FIGS. 2 and 12 , in contrast to  FIG. 11 , the sensing and lighting device  200  in  FIG. 12  is positioned in a side air duct  1202 . The area below the ceiling  1104  may be an area that is occupied by people or that is connected to such an area. The sensing and lighting device  200  may be positioned in an inside space  1206  of the air duct  1202  proximal to an opening of the air duct  1102 . As air flows past the sensor  104  of the lighting device  200  on the outside of the lighting fixture  202 , the sensor  104  may monitor the quality of the air as described above with respect to  FIG. 2 . In some example embodiments, the air duct  1102  may be a supply air duct (e.g., an HVAC supply air duct). 
     Although  FIG. 12  illustrates the sensing and lighting device  200  of  FIG. 2  installed in a ceiling, in some alternative embodiments, the sensing and lighting devices  100 ,  300 ,  500  may instead be installed in the ceiling in a similar manner. In some alternative embodiments, the sensor  104  may be in the path of the return air at a location other than shown in  FIG. 12  without departing from the scope of this disclosure. 
       FIG. 13  illustrates a network  1300  of the sensing and lighting devices  1306 ,  1308 ,  1310  according to an example embodiment. For example, each one of the sensing and lighting devices  1306 ,  1308 ,  1310  may correspond to the sensing and lighting device  200  of  FIG. 2 . Alternatively, the sensing and lighting devices of  FIGS. 1, 3, and 5  may be included the network  1300  instead of or in addition to the sensing and lighting device  200 . 
     In some example embodiments, the network  1300  includes a wireless control device  1302 . For example, the wireless control device  1302  may be a mobile phone, a laptop, a table, or a wall mounted control device with a display, etc. The sensing and lighting devices  1306 ,  1308 ,  1310  may wirelessly communicate with the wireless control device  1302  via wireless signals  1304 . For example, the control device  1302  may wirelessly control the lighting-related operations of the sensing and lighting devices  1306 ,  1308 ,  1310 . In some example embodiments, the sensing and lighting devices  1306 ,  1308 ,  1310  may communicate air quality information, hazard condition information, etc. wirelessly to the wireless control device  1302 , and may receive information and commands wirelessly from the wireless control device  1302 . For example, the sensing and lighting devices  1306 ,  1308 ,  1310  may wirelessly receive instructions to stop providing visual and/or audio notification. In general, the wireless control device  1302  may communicate wirelessly with the sensing and lighting devices  1306 ,  1308 ,  1310  in the same manner as described above. 
     In some example embodiments, one or more of the sensing and lighting devices  1306 ,  1308 ,  1310  may flash their respective lights to provide notification of a hazard condition that, for example, is detected by the respective sensor  104  of the one or more of the sensing and lighting devices  1306 ,  1308 ,  1310 . In some example embodiments, fewer than all the sensing and lighting devices  1306 ,  1308 ,  1310  may flash their respective lights to provide notification as well as a guide to an exit, to a particular sensing and lighting device that detected the hazard, etc. 
     In some example embodiments, the sensor  104  of each sensing and lighting devices  1306 ,  1308 ,  1310  may wirelessly communicate with the wireless control device  1302  or with each other using the transceivers of the sensing and lighting devices  1306 ,  1308 ,  1310 . Alternatively, the sensor  104  of each sensing and lighting devices  1306 ,  1308 ,  1310  may wirelessly communicate with the wireless control device  1302  or with each other on a separate network without using the transceivers of the sensing and lighting devices  1306 ,  1308 ,  1310 . In some alternative embodiments, the sensing and lighting devices  1306 ,  1308 ,  1310  may use a wired network (e.g., an Ethernet network) to communicate with the control device  1302  or with another remote control device. For example, the sensor of each sensing and lighting devices  1306 ,  1308 ,  1310  may be communicate with the control device  1302  over a wired network instead of a wireless network. 
     Although three sensing and lighting devices are shown in  FIG. 13 , in alternative embodiments, the network  1300  may include fewer or more than three sensing and lighting devices. In some example embodiments, the network  1300  may include other network components such as routers without departing from the scope of this disclosure. In some example embodiments, the network  1300  may operate in compliance with one or more wireless communications standards such as Wi-Fi, ZigBee, etc. 
     Although  FIG. 13  illustrates the sensing and lighting devices  200  of  FIG. 2  installed in a ceiling, in some alternative embodiments, the network  1300  may include one or more of the sensing and lighting devices  100 ,  300 ,  500  installed in the ceiling in a similar manner instead of or in addition to one or more of the sensing and lighting devices  200 . 
     Although particular embodiments have been described herein in detail, the descriptions are by way of example. The features of the example embodiments described herein are representative and, in alternative embodiments, certain features, elements, and/or steps may be added or omitted. Additionally, modifications to aspects of the example embodiments described herein may be made by those skilled in the art without departing from the spirit and scope of the following claims, the scope of which are to be accorded the broadest interpretation so as to encompass modifications and equivalent structures.