Patent Publication Number: US-2023160848-A1

Title: System and method for determining an ambient concentration of compositions for bathroom cleaning

Description:
TECHNICAL FIELD 
     The present disclosure relates generally to sensors. More particularly, the present disclosure relates to a system and method for determining an ambient concentration of compositions for bathroom cleaning. 
     BACKGROUND 
     A plurality of parameters can be correlated to the cleanliness of a bathroom. An entity managing the bathroom is not able to measure certain parameters and determine how each parameter affects the cleanliness of the bathroom. 
     SUMMARY 
     Existing systems and methods used for monitoring a toilet and the cleanliness of a bathroom suffer from disadvantages. For example, this disclosure recognizes that existing systems do not employ one or more sensors to measure a parameter related to the bathroom. The existing systems and methods are not able to determine when the bathroom has been cleaned or requires cleaning based on measurements from the one or more sensors. 
     The disclosed system provides several practical applications and technical advantages that overcome the previously discussed technical problems. For example, the disclosed system provides a practical application by employing an alerting system that is configured to collect information about the number of instances of a decrease in water in the toilet tank and the number of instances the door transitions from an open and closed position, determine whether certain conditions are met or if thresholds are exceeded, and to alert a user to take an action within a given period of time, such as cleaning the bathroom. In this example, a distance sensor may be used to determine iterative distance measurements of water level within the toilet tank over a period of time. Those distance measurements may be compared to a threshold over a period of time. Those distance measurements may further be used to calculate a ratio of the number of instances of a decrease in water level in the toilet tank to the number of instances where a user opens the door to the bathroom. The alerting system may transmit the alert to a user device in order to prompt a user to clean the toilet associated with the toilet tank or to clean the bathroom if certain conditions are met. 
     The alerting system monitors how many times a toilet in a bathroom has been flushed over a period of time in order to schedule a cleaning of the toilet. For example, users may utilize the toilet during an interaction with an entity. The entity may be a store offering goods for purchase by the users. In this example, the entity may be a convenience store where the users may utilize the toilet before or after purchasing goods from the entity (i.e., snacks, beverages, etc.). The convenience store may have a schedule for cleaning the bathroom, such as once per day. Over time, the bathroom may get increasingly dirty, and the scheduled cleaning may be ineffective in maintaining a clean bathroom for the users. To maintain a clean bathroom, the alerting system identifies when to alert the entity that the bathroom needs cleaning based on the number of times a toilet has been flushed. There may be an inverse relationship between the number of times a toilet has been flushed and cleanliness of the bathroom. For example, as the number of times the toilet flushes increases, the cleanliness of the bathroom decreases. 
     Further, the alerting system monitors how many times a door to the bathroom has opened and closed over a period of time in order to schedule a cleaning for the toilet. For example, users may open and close a door each time before utilizing the bathroom. Once in the bathroom, the user may utilize the toilet. If the toilet is not working or is too dirty for use, the user may exit the bathroom through the door. The alerting system identifies this event by monitoring the door and identifying that the toilet was not flushed while the user was in the bathroom. The entity managing the bathroom (i.e., the convenience store) determines that the toilet is not working or is too dirty for use when the alerting system determines that the number of times the toilet has flushed in relation to the number of times the door has been opened and closed is below a certain ratio. 
     In an embodiment, a system for diagnostic analysis of a bathroom over time intervals comprises a sensor disposed within a toilet tank. The sensor comprises a laser diode, a photodetector, and a first processor. The laser diode is operable to produce a laser beam pulse that travels towards a water level within the toilet tank, wherein the laser beam pulse is reflected back to the sensor. The photodetector is operable to receive the reflected laser beam pulse. The first processor is communicatively coupled to the laser diode and to the photodetector. The first processor is configured to determine a distance measurement based on a difference in time between production of the laser beam pulse and reception of the reflected laser beam pulse and to transmit the distance measurement across a network. The system further comprises a computer system communicatively coupled to the sensor using the network, comprising a memory and a second processor. The memory is operable to store door information comprising a number of instances wherein a door changes from a first position to a second position within a period of time, store a threshold ratio of a number of instances of a decrease in the water level to the number of instances wherein the door changes from the first position to the second position, and store a setpoint corresponding to an initial water level in the toilet tank. The second processor is operably coupled to the memory and configured to receive the distance measurement from the network. The second processor is further configured to determine an instance of the decrease in the water level in the toilet tank based on a comparison of the received distance measurement to the setpoint and determine a plurality of instances of the decrease in the water level within the period of time. The second processor is further configured to calculate a ratio of the determined number of the plurality of instances of the decrease in the water level to the number of instances wherein the door changes from the first position to the second position based on the door information stored in the memory. The second processor is further configured to compare the calculated ratio to the threshold ratio and to send an alert for display on a user device when the calculated ratio is less than the threshold ratio. 
     The disclosed system provides further practical applications and technical advantages by employing an alerting system that is configured to collect information about the concentration of one or more compounds, such as volatile organic compounds (VOC), present in the bathroom, determine whether certain conditions are met or if thresholds are exceeded, and to alert a user to take an action within a given period of time, such as cleaning the bathroom. 
     The alerting system determines the concentration of one or more VOCs within the ambient environment of the bathroom in order to monitor cleaning of the bathroom. For example, the entity managing the bathroom (i.e., the convenience store) may have a schedule for cleaning the bathroom, such as once per twelve hours. Someone associated with the entity, such as an employee, may be too busy performing other tasks to comply with the cleaning schedule. To monitor the cleaning of the bathroom for compliance, the alerting system may register an event associated with cleaning the bathroom based on different threshold values for various cleaning solutions. However, the employee may forget to clean the bathroom, may spill chemicals in an attempt to clean the bathroom, perform a cursory cleaning, or try to deceive the system in order to perform other tasks. 
     In another embodiment, a system for determining an ambient concentration of a volatile organic compound comprises a sensor disposed proximate to an exhaust fan operable to receive an airflow from the exhaust fan. The sensor comprises a light source, a pair of electrodes, and a first processor. The light source is operable to produce a light configured to ionize one or more molecules of the volatile organic compound present in the airflow. The pair of electrodes is operable to receive the ionized one or more molecules and to generate an electrical current proportional to a concentration of the ionized one or more molecules. The first processor is communicatively coupled to the pair of electrodes and is configured to determine a concentration measurement for the volatile organic compound based at least in part upon the electrical current generated by the pair of electrodes and to transmit the concentration measurement across a network. The system further comprises a computer system communicatively coupled to the sensor, comprising a memory and second processor. The memory is operable to store a first threshold for the concentration measurement associated with an event of cleaning a bathroom and store a second threshold for the concentration measurement, wherein the second threshold is greater than the first threshold. The second processor is configured to receive the concentration measurement from the network within a first period of time and to compare the received concentration measurement to the first threshold. The second processor is further configured to compare the received concentration measurement to the second threshold and to instruct the memory to store an indication that the bathroom was cleaned in response to a determination that the received concentration measurement is greater than the first threshold and less than the second threshold. 
     A practical application is provided for identifying a current state of cleanliness for the bathroom and maintaining an optimal state of cleanliness based on the measurements provided by the sensors. For example, during a period of time, the alerting system receives information from various sensors associated with the bathroom. The alerting system can autonomously determine whether one or more conditions have been met before generating and transmitting and alert prompting an action be taken. The alerting system can maintain compliance for scheduled cleaning and identify when a toilet may need to be serviced based on received information and threshold numbers or ratios. 
     Certain embodiments of the present disclosure may include some, all, or none of these advantages. These advantages and other features will be more clearly understood from the following detailed description taken in conjunction with the accompanying drawings and claims. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       For a more complete understanding of this disclosure, reference is now made to the following brief description, taken in connection with the accompanying drawings and detailed description, wherein like reference numerals represent like parts. 
         FIG.  1    is a schematic diagram of an example automatic alerting system; 
         FIG.  2    is a flow diagram illustrating a first example operation of the alerting system of  FIG.  1   ; and 
         FIG.  3    is a flow diagram illustrating a second example operation of the alerting system of  FIG.  1   . 
     
    
    
     DETAILED DESCRIPTION 
     This disclosure provides solutions to the aforementioned and other problems of previous technology through an automatic alerting process for diagnostic analysis of a toilet over time intervals. The disclosure further provides an automatic alerting process for determining an ambient concentration of compositions for bathroom cleaning. 
     Automatic Alerting System 
       FIG.  1    illustrates a schematic diagram of an example automatic alerting system  100 . As illustrated in  FIG.  1   , the automatic alerting system  100  includes a computer system  102 , a user device  104 , a network  106 , and one or more sensors  108 . Computer system  102  is communicatively coupled to user device  104  and the one or more sensors  108  via the network  106  using any appropriate wired or wireless telecommunication technology. 
     Computer system  102  may be any appropriate computing system in any suitable physical form. As example and not by way of limitation, computer system  102  may be an embedded computer system, a system-on-chip (SOC), a single-board computer system (SBC) (such as, for example, a computer-on-module (COM) or system-on-module (SOM)), a desktop computer system, a laptop or notebook computer system, a mainframe, a mesh of computer systems, a mobile telephone, a personal digital assistant (PDA), a server, a tablet computer system, an augmented/virtual reality device, or a combination of two or more of these. Where appropriate, computer system  102  may include one or more computer systems  102 ; be unitary or distributed; span multiple locations; span multiple machines; span multiple data centers; or reside in a cloud, which may include one or more cloud components in one or more networks. Where appropriate, one or more computer systems  102  may perform without substantial spatial or temporal limitation one or more steps of one or more methods described or illustrated herein. As an example and not by way of limitation, one or more computer systems  102  may perform in real time or in batch mode one or more steps of one or more methods described or illustrated herein. One or more computer systems  102  may perform at different times or at different locations one or more steps of one or more methods described or illustrated herein, where appropriate. The computer system  102  may include a memory  110  operable to store information and/or provide access to application(s), wherein the memory  110  includes software instructions that, when executed by a processor  112 , cause the computer system  102  to perform one or more functions described below. Computer system  102  may be physically located within the same physical building in which one or more sensors  108  are located, or physically located at a location remote from the physical building in which one or more sensors  108  are located. For example, in certain embodiments, computer system  102  may be located in one or more remote servers (e.g., in the cloud). Details of the operations of the computer system  102  are described in conjunction with  FIGS.  2 - 3   . 
     Processor  112  is any electronic circuitry, including, but not limited to a microprocessor, an application specific integrated circuits (ASIC), an application specific instruction set processor (ASIP), and/or a state machine, that communicatively couples to memory  110  and controls the operation of computer system  102 . Processor  112  may be 8-bit, 16-bit, 32-bit, 64-bit or of any other suitable architecture. Processor  112  may include an arithmetic logic unit (ALU) for performing arithmetic and logic operations, processor registers that supply operands to the ALU and store the results of ALU operations, and a control unit that fetches instructions from memory and executes them by directing the coordinated operations of the ALU, registers and other components. Processor  112  may include other hardware that operates software to control and process information. Processor  112  executes software stored in memory to perform any of the functions described herein. Processor  112  controls the operation and administration of computer system  102  by processing information received from one or more sensors  108 , network  106 , user device  104 , and memory  110 . Processor  112  may be a programmable logic device, a microcontroller, a microprocessor, any suitable processing device, or any suitable combination of the preceding. Processor  112  is not limited to a single processing device and may encompass multiple processing devices. 
     Memory  110  may store, either permanently or temporarily, data (such as distance measurements  126  or concentration measurements  160  described further below), user preferences, business rules, operational software such as automatic alerting module  114  (described further below) and thresholding module  116  (described further below), or other information for processor  112 . Memory  110  may include any one or a combination of volatile or non-volatile local or remote devices suitable for storing information. For example, memory  110  may include random access memory (RAM), read only memory (ROM), magnetic storage devices, optical storage devices, or any other suitable information storage device or a combination of these devices. 
     User device  104  is any appropriate device for communicating with components of computer system  102  over network  106 . For example, user device  104  may be a handheld computing device such as a smartphone, wearable computer glasses, a smartwatch, a tablet computer, a laptop computer, and the like. User device  104  may include an electronic display, a processor such as processor  112 , and memory such as memory  110 . The electronic display of user device  104  may display an alert  118  (described further below) that is provided by computer system  102 . For example, in certain embodiments, user device  104  may generate a pop-up message that includes the alert  118 , and automatically display the pop-up message on a screen of user device  104 . In some embodiments, user device  104  may generate a sound and/or vibration in response to receiving alert  118 . In certain embodiments, user device  104  may display a graphical user interface (GUI) on a screen of user device  104  within which the alert  118  may be displayed. In further examples, user device  104  may receive alert  118  through an email and/or text message. The alert  118  may indicate that a condition has been met and may signal for an event to occur. After receiving the alert  118 , a user associated with the user device  104  may proceed to take action according to the alert  118 . 
     In certain embodiments, user device  104  may receive measurements made by one or more sensors  108  and use the measurements to monitor a cleaning schedule of a bathroom and to determine whether to clean the bathroom or a toilet located in the bathroom. In these embodiments, the one or more sensors  108  may directly communicate with the user device  104  instead of with the computer device  102 . For example, in such embodiments, a memory  117  of user device  104  may include instructions (e.g., instructions  140  and/or  142  described in detail below) that, when executed by a processor  119  of user device  104 , enable the device to determine, based on the received measurements, whether to clean the bathroom or a toilet located in the bathroom, or whether a cleaning has occurred in view of the cleaning schedule. For example, instructions stored in memory  117  may indicate that: a number of times a toilet has flushed exceeds a threshold, a ratio of the number of times the toilet has flushed to a number of times a door to the bathroom has opened is less than a threshold ratio, and a concentration of a volatile organic compound present in the bathroom exceeds a threshold. In response to any one of these events, user device  104  may automatically generate and display an alert for a user associated with user device  104 . 
     Network  106  allows communication between and amongst the various components of system  100 . For example, computer system  102 , user device  104 , and one or more sensors  108  may communicate via network  106 . This disclosure contemplates network  106  being any suitable network operable to facilitate communication between the components of system  100 . Network  106  may include any interconnecting system capable of transmitting audio, video, signals, data, messages, or any combination of the preceding. Network  106  may include all or a portion of a local area network (LAN), a wide area network (WAN), an overlay network, a software-defined network (SDN), a virtual private network (VPN), a packet data network (e.g., the Internet), a mobile telephone network (e.g., cellular networks, such as 4G or 5G), a Plain Old Telephone (POT) network, a wireless data network (e.g., WiFi, WiGig, WiMax, etc.), a Long Term Evolution (LTE) network, a Universal Mobile Telecommunications System (UMTS) network, a peer-to-peer (P2P) network, a Bluetooth network, a Near Field Communication (NFC) network, a Zigbee network, and/or any other suitable network, operable to facilitate communication between the components. 
     Example Automatic Alerting System for Diagnostic Analysis of a Toilet Over Time Intervals 
     The automatic alerting system  100  may be implemented to monitor how many times a toilet in a bathroom has been flushed over a period of time in order to schedule a cleaning of the toilet. For example, users may utilize the toilet during an interaction with an entity. The entity may be a store offering goods for purchase by the users. In this example, the entity may be a convenience store where the users may utilize the toilet before or after purchasing goods from the entity (i.e., snacks, beverages, etc.). The convenience store may have a schedule for cleaning the bathroom, such as once per day. Over time, the bathroom may get increasingly dirty, and the scheduled cleaning may be ineffective in maintaining a clean bathroom for the users. To maintain a clean bathroom, the automatic alerting system  100  may identify when to alert the entity that the bathroom needs cleaning based on the number of times a toilet has been flushed. There may be an inverse relationship between the number of times a toilet has been flushed and cleanliness of the bathroom. For example, as the number of times the toilet flushes increases, the cleanliness of the bathroom decreases. 
     In one or more embodiments, this process uses the sensor  108   a  to determine a distance to a level of water  120  contained within a toilet tank  122  disposed in a bathroom  124 . The toilet tank  122  may be a structure serving as a containment chamber of any suitable toilet operable to receive water  120  from an external source and contain the water  120  until a user actuates the toilet to allow for the water  120  to flow out of the toilet tank  122  (i.e., an event of a flush). As illustrated, computer system  102  may receive data in the form of distance measurements  120  that are generated by sensor  108   a.  The computer system  102  further generates the alert  118  for display on the user device  104  based on comparing the distance measurements  126  to a setpoint  128  (described further below) stored in the memory  110 . In general, the computer system  102  may perform an alerting process based on the received distance measurements  126 . 
     The sensor  108   a  is any appropriate device for sensing or measuring the physical distance to an object. For example, sensor  108   a  may be a time of flight (ToF) sensor that utilizes a laser to produce a beam of infrared light that is bounced off an object and returned to the sensor  108   a  in order to measure distance to the object. Sensor  108   a  may include a laser diode  130 , a photodetector  132 , and a sensor processor  134 . In a particular embodiment, the laser diode  130  may produce a laser beam  136  that travels towards a level of water  120 , wherein the laser beam  136  is reflected off of the water  120  to travel back to the sensor  108   a.  The laser diode  130  may produce pulses of laser beams  130  at a pre-determined frequency. The photodetector  132  may be any appropriate device operable to receive each reflected laser beam  136 . In one or more embodiments, the sensor processor  134  may be communicatively coupled to the laser diode  130  and to the photodetector  132 . The sensor processor  134  may determine a distance measurement  126  based on a difference in time between production of the laser beam  136  by the laser diode  130  and reception of the reflected laser beam  136  by the photodetector  132 . The sensor processor  134  may further transmit each distance measurement  126  across the network  106 . 
     In general, sensor  108   a  provides the distance measurement  126  to computer system  102 . Distance measurement  126  may comprise any appropriate distance value (e.g., inches or millimeters). In some embodiments, distance measurement  126  is provided automatically by sensor  108   a  at periodic intervals (e.g., every five minutes). In other embodiments, distance measurement  126  is provided by sensor  108   a  when requested by computer system  102 . 
     In some embodiments, sensor  108   a  may operate as an Internet-of-Things (IoT) sensor. In general, IoT describes a network of physical objects that are embedded with sensors, software, and other technologies for the purpose of connecting and exchanging data with other devices and systems over the Internet, or any suitable network. In embodiments where sensor  108   a  is an IoT sensor, automatic alerting system  100  may include a gateway  138  for communicating with each one of sensors  108 . Gateway  138  may be any appropriate IoT gateway, computer system, or electronic device that is capable of wirelessly communicating with sensor  108   a  using any appropriate IoT communications protocol. Without limitations, the IoT communications protocol may include message queuing telemetry transport (MQTT), constrained application protocol (CoAP), advanced message queuing protocol (AMQP), data-distribution service (DDS), Zigbee, Z-Wave, lightweight machine-to-machine (LwM2M), or any combinations thereof. For example, sensor  108   a  may wirelessly transmit distance measurement  126  to gateway  138 , and gateway  138  may in turn send distance measurement  126  to computer system  102  via network  106 . In other embodiments, the sensor  108   a  may not be an IoT sensor. In embodiments where the sensor  108   a  is not operable as an IoT sensor, sensor  108   a  may transmit distance measurement  126  directly to computer system  102  via network  106  (i.e., without utilizing gateway  138 ). 
     For example, in a particular embodiment, the sensor  108   a  may be disposed or mounted within the toilet tank  122  above the level of water  120 . The computer system  102  may calibrate the sensor  108   a  to provide measurements relative to the toilet tank  122  by instructing the sensor  108   a  to perform a first distance measurement  126   a  to determine a distance from the level of water  120  to the sensor  108   a  at an initial level (i.e., when the toilet tank  122  has not been actuated to flush the water  120 ). The sensor  108   a  may transmit the first distance measurement  126   a  to the computer system  102  for storage as the setpoint  128 . The computer system  102  may determine an instance of a decrease in the level of water  120  (for example, an event associated with flushing the toilet tank  122 ) based on a comparison between a received distance measurement  126  and the setpoint  128 . For example, if the received distance measurement  126  is greater than the setpoint  128 , the computer system  102  determines that an event associated with flushing the toilet tank  122  has occurred. In this example, the greater value of the received distance measurement  126  indicates that there was a decrease in the level of water  120  relative to the setpoint  128 . As a user flushes the toilet, the level of water  120  decreases in the toilet tank  122  and flows further down through the toilet. 
     During operation, the sensor  108   a  may determine a plurality of distance measurements  126  from the level of the water  120  to the sensor  108   a  (a “water level”), wherein the computer system  102  may receive the plurality of distance measurements  126  transmitted over the network  106 . The computer system  102  may determine a plurality of instances of the decrease in the level of water  120  based on the received plurality of distance measurements  126 . In embodiments, the determined plurality of instances of the decrease in the level of water  120  may be compared to a threshold number set by the thresholding module  116 . For example, the threshold number represents the allowable number of flushes for a toilet before the entity cleans the toilet. The threshold number may be any suitable value (for example, 5, 10, 15, etc.). In an example, if the determined plurality of instances of the decrease in the level of water  120  is six and the threshold number is five, the computer system  102  may generate and transmit the alert  118 . 
     Thresholding module  116  represents any suitable set of instructions, logic, or code embodied in a computer-readable storage medium. For example, thresholding module  116  may be embodied in memory  110 , a disk, a CD, or a flash drive. In particular embodiments, thresholding module  116  may include thresholding instructions  140  (e.g., a software application) executable by processor  112  to perform one or more of the functions described herein. In general, thresholding instructions  140  may determine the threshold number of instances of the decrease in the level of water  120  for a period of time. 
     The computer system  102  may transmit the alert  118  to the user device  104  when the determined plurality of instances of the decrease in the level of water  120  is greater than the threshold number. For example, the alert  118  may be generated and transmitted when the computer system  102  determines that a toilet has flushed twenty-one times and the threshold number is twenty during a period of six hours. The alert  118  may indicate that the determined plurality of instances of the decrease in the level of water  120  has exceeded the threshold number within a period of time and prompt an event, such as cleaning the toilet associated with the toilet tank  122 . In another example, a toilet may not be working or may be too dirty for use. There may be a determination that the toilet has flushed five times within the first hour of a period of six hours. If a designated time interval is two hours and there is no subsequent flush after that time interval (i.e., after the third hour), the computer system  102  may generate and transmit the alert  118 . The alert  118  may indicate that there has been no change in the determined number of the plurality of instances of the decrease in the level of water  120  over a time interval and prompt an event, such as cleaning and/or performing maintenance on the toilet associated with the toilet tank  122 . In these examples, the alert  118  may be generated and transmitted via the automatic alerting module  114  of the computer system  102 . 
     Automatic alerting module  114  represents any suitable set of instructions, logic, or code embodied in a computer-readable storage medium. For example, automatic alerting module  114  may be embodied in memory  110 , a disk, a CD, or a flash drive. In particular embodiments, automatic alerting module  114  may include alerting instructions  142  (e.g., a software application) executable by processor  112  to perform one or more of the functions described herein. In general, automatic alerting module  114  sends alert  118  for display on user device  104  via network  106 . As described, alert  118  is generated by automatic alerting module  114  based, at least in part, on the distance measurements  126  from sensor  108   a.  The alerting instructions  142  may generate and transmit the alert  118  when the determined plurality of instances of the decrease in the level of water  120  has exceeded the threshold number within a period of time, when there has been no change in the determined number of the plurality of instances of the decrease in the level of water  120  over a time interval, or both. 
     In another example, the automatic alerting system  100  may be implemented to monitor how many times a door to the bathroom has opened and closed over a period of time in order to schedule a cleaning for the toilet. For example, users may open and close a door each time before utilizing the bathroom. Once in the bathroom, the user may utilize the toilet. If the toilet is not working or is too dirty for use, the user may exit the bathroom through the door without using the toilet. The automatic alerting system  100  may identify this event by monitoring the door and identifying that the toilet was not flushed while the user was in the bathroom. The entity managing the bathroom (i.e., the convenience store) may determine that the toilet is not working or is too dirty for use when the automatic alerting system  100  determines that the number of times the toilet has flushed in relation to the number of times the door has been opened and closed is below a certain ratio. 
     The automatic alerting system  100  may include any suitable sensors or switches to monitor the opening and closing of a door. In particular embodiments, a switch  144  may be used in conjunction with the sensor  108   a  to generate the alert  118  to be displayed on the user device  104 . For example, in a particular embodiment, the switch  144  may be disposed or coupled to a door frame  146  associated with the bathroom  124 . A door  148  may be coupled to the door frame  146  operable to rotate about a side of the door frame  146  between a first position (i.e., closed) and a second position (i.e., open). In certain embodiments, the door  148  and door frame  146  may serve as an entryway into and out of the bathroom  124 . In other embodiments, the door  148  and door frame  146  may serve as an entryway into and out of an individual stall within the bathroom  124 . The switch  144  may transmit a signal  150  indicating an instance of transition between positions for the door  148  to the computer system  102  for storage as door information  152 . 
     Switch  144  is any appropriate device for determining a condition based on transitioning between positions due to manual operation or in response to a determined parameter. For example, switch  144  may be a reed switch operable to open or close based on proximity to a magnetic field. In other examples, the switch  144  may be a toggle switch, rotary switch, biased switch, slide switch, or an electronic switch. Switch  144  may include a pair of contacts  154  and a switch processor  156 . In a particular embodiment, the switch  144  may be coupled to the door frame  146 . The pair of contacts  154  may be in a closed position when in proximity to a magnet  158  coupled to the door  148 , wherein the pair of contacts  154  transitions from the closed position to an open position as the door  148  changes from the first position to the second position (for example, by rotating along a side of the door frame  146 ). In one or more embodiments, the switch processor  156  may be communicatively coupled to the pair of contacts  154 . The switch processor  156  may determine an instance of transition from the closed position to the open position. The switch processor  156  may further transmit each instance of transition across the network  106 . In other embodiments, the switch  144  may be communicatively coupled to a gateway  138 , wherein the gateway  138  may send the instance of transition to computer system  102  via network  106 . 
     In an example, the computer system  102  may identify when the toilet is inoperable or is dirty based on a ratio of the number of flushes to the number of times the door  148  opens and closes. For example, if the door opens and closes a certain number of times more than the number of times the toilet flushes, the computer system  102  may identify that the entity operating the bathroom  124  (i.e., the convenience store) should check on the toilet. A user may enter and exit through the door  148  without flushing the toilet in situations such as when the toilet is too dirty for use, when the toilet is not working, or both. The computer system  102  may identify these aforementioned situations based on calculating that ratio and comparing the ratio to a threshold ratio set by the entity. 
     The computer system  102  may determine a ratio of the determined number of the plurality of instances of the decrease in the level of water  120  to a number of instances wherein the door  148  changes from the first position to the second position based on the stored door information  152 . In embodiments, the determined ratio may be compared to a stored threshold ratio. The stored threshold ratio may take into account situations wherein a user enters the bathroom  124  to use a sink or mirror instead of the toilet. The computer system  102  may then transmit the alert  118  to the user device  104  when the determined ratio is less than the threshold ratio. In these examples, the threshold ratio may be associated with the door  148  being an entryway into and out of the bathroom  124 , an entryway into and out of an individual stall within the bathroom  124 , or a combination thereof. In an example, the computer system  102  may determine that a toilet has flushed six times and the door  148  has opened and closed ten times during a period of two hours. In this example, the stored threshold ratio may be set at 7:10. The alert  118  may indicate that the determined ratio of 6:10 is less than the threshold ratio of 7:10 within a period of time and prompt an event, such as cleaning the toilet associated with the toilet tank  122  and/or maintenance of the toilet. This example may indicate that the toilet was dirty, unusable, not operating, or a combination thereof. 
     Example Automatic Alerting System for Determining an Ambient Concentration of Compositions for Bathroom Cleaning 
     The automatic alerting system  100  may be implemented to determine volatile organic compounds (VOCs) within the ambient environment of the bathroom  124  in order to monitor cleaning of the bathroom  124 . For example, the entity managing the bathroom  124  (i.e., the convenience store) may have a schedule for cleaning the bathroom  124 , such as once per twelve hours. Someone associated with the entity, such as an employee, may be too busy performing other tasks to comply with the cleaning schedule. To monitor the cleaning of the bathroom  124  for compliance, the automatic alerting system  100  may register an event associated with cleaning the bathroom  124  based on different threshold values for various cleaning solutions. However, the employee may forget to clean the bathroom  124 , may spill chemicals in an attempt to clean the bathroom  124 , perform a cursory cleaning, or try to deceive the system  100  in order to perform other tasks. 
     In one or more embodiments, the automatic alerting system  100  may generate the alert  118  based, at least partly on, concentration measurements  160  of potential volatile organic compounds (VOCs) present in the bathroom  124 . The alert  118  may be generated based solely or partly on the concentration measurements  160 . For example, the sensor  108   b  may be disposed proximate to an exhaust fan  162  operable to receive an airflow from the exhaust fan  162 . The exhaust fan  162  may direct air out from the bathroom  124 . The sensor  108   b  may determine a concentration of one or more VOCs within the airflow received from the exhaust fan  162 . 
     Sensor  108   b  is any appropriate device for sensing or measuring a concentration of one or more compounds, such as VOCs. For example, sensor  108   b  may be a VOC sensor that utilizes a light to ionize one or more molecules received by electrodes in order to measure a concentration of the one or more compounds. Without limitations, the sensor  108   b  may be a photoionization detector, a flame ionization detector, a metal oxide semiconductor sensor, or a combination thereof. Sensor  108   b  may include a light source  164 , a pair of electrodes  166 , and a sensor processor  168 . In a particular embodiment, the light source  164  may produce a light (for example, ultraviolet light) configured to ionize one or more molecules of the VOC present in the airflow. The pair of electrodes  166  may receive the ionized one or more molecules and to generate an electrical current proportional to a concentration of the received, ionized one or more molecules. In one or more embodiments, the sensor processor  168  may be communicatively coupled to the light source  164  and the pair of electrodes  166 . The sensor processor  168  may determine a concentration measurement  160  for the VOC based at least in part upon the electrical current generated by the pair of electrodes  166 . The sensor processor  168  may further transmit each concentration measurement  160  across the network  106 . In certain embodiments, sensor  108   b  may be communicatively coupled to a gateway  138 , wherein the gateway  138  may send the concentration measurement  160  to computer system  102  via network  106 . 
     In general, sensor  108   b  provides the concentration measurement  160  to computer system  102 . Concentration measurement  160  may comprise any appropriate concentration value (e.g., parts per million). In some embodiments, concentration measurement  160  is provided automatically by sensor  108   b  at periodic intervals (e.g., every five minutes). In other embodiments, concentration measurement  160  is provided by sensor  108   b  when requested by computer system  102 . 
     The computer system  102  may receive a concentration measurement  160  from the sensor  108   b  within a period of time. During operations, computer system  102  may compare the received concentration measurement  160  to a first threshold associated with an event of cleaning the bathroom  124 . In embodiments, if the received concentration measurement  160  is not greater than the first threshold, the system  100  may continue to operate within the period of time by iteratively determining concentration measurements  160  and comparing the concentration measurements  160  to the first threshold. If there is a transition from the current period of time to a subsequent period of time, the computer system  102  may generate and transmit the alert  118  to the user device  104  indicating that the bathroom  124  was not cleaned within the previous period of time. 
     For example, the sensor  108   b  may monitor for concentrations of ammonia and ethanol. In this example, ammonia or ethanol may be present in aerosolized or spray cleaner solutions, in cleaner solutions for application on the floor and/or tiles of the bathroom  124 , in a toilet associated with the toilet tank  122 , and any combination thereof. Further, a particular cleaning solution may be comprised of any suitable volumetric concentration of ammonia. For example, one cleaning solution may comprise of 0.1%, 0.2%, or 0.3% ammonia. The computer system  102  may store different values for the first threshold based on different compounds. A first threshold for ammonia may comprise sub-thresholds, wherein each sub-threshold is associated with a particular cleaning solution. For example, a first sub-threshold for ammonia present in aerosolized or spray cleaner solutions may be within a range of about 0.5 parts per million (ppm) to about 3 ppm. A second sub-threshold for ammonia present in cleaner solutions comprising 0.1% ammonia may be within a range of about 16 ppm to about 28 ppm. A third sub-threshold for ammonia present in cleaner solutions comprising 0.2% ammonia may be within a range of about 36 ppm to about 90 ppm. A fourth sub-threshold for ammonia present in cleaner solutions comprising 0.3% ammonia may be within a range of about 125 ppm to about 150 ppm. With reference to ethanol, a first threshold may be within a range of about 0.5 ppm to about 50 ppm. 
     The computer system  102  may be further operable to compare the concentration measurement  160  to a second threshold if the concentration measurement  160  is determined to be greater than the first threshold. For example, the second threshold for ammonia and ethanol may be about 150 ppm. In certain embodiments, the second threshold is indicative of either an event of a spill of one or more chemicals occurring within the bathroom  124  or with an event of tampering of the sensor  108   b.  As the first threshold has already been surpassed by the concentration measurement  160  to indicate that the bathroom  124  has been cleaned, an increasing value of the concentration measurements  160  may indicate further production of one or more compounds, such as VOCs, in the bathroom  124 . In an example event of a spill, one or more chemicals may continue to produce one or more compounds until cleaned and removed from the bathroom. In an example event of tampering with the sensor  108   b,  an employee associated with the entity may continue to produce one or more compounds by spraying an aerosolized compound towards the sensor  108  for a period of time. 
     To distinguish between events, the computer system  102  may determine a moving average of a concentration of one or more compounds, such as VOCs, present in the airflow over a given time period (for example, 10 minutes). The moving average is representative of the average concentration of one or more compounds within a rolling window of time over the period of time. The moving average may smooth out short-term fluctuations in the concentration measurements and highlight longer-term trends. In embodiments, the moving average may be simple, cumulative, exponential, weighted, or any combination thereof. For example, the rolling window of time may be designated for 2 minutes for an overall period of time of 10 minutes. In this example, the computer system  102  may determine the following concentrations of ammonia: 125 ppm at 15 seconds, 125 ppm at 30 seconds, 127 ppm at 45 seconds, 135 ppm at 60 seconds, 135 ppm at 75 seconds, 135 ppm at 90 seconds, 130 ppm at 105 seconds, 135 ppm at 120 seconds, 140 ppm at 135 seconds, and 145 ppm at 150 seconds. The average concentration of ammonia within the rolling window of time for the initial two minutes of operation is 130.875 ppm (i.e., average of the first eight concentration measurements). As time increases, the computer system  102  may adjust the average concentration to include newer concentration measurements. For example, at a time of 135 seconds, the rolling window may shift from 0-120 seconds to 15-135 seconds to maintain a rolling window of time of two minutes. The average concentration of ammonia within the updated rolling window of time is 132.75 ppm (i.e., average of the concentration measurements taken from 15-135 seconds). 
     The computer system  102  may then compare the determined moving average to the second threshold. If the determined moving average comprises an average concentration that is less than the second threshold, the computer system  102  may generate and transmit the alert  118  to the user device  104  indicating that the sensor  108   b  has been tampered. The average concentration being less than the second threshold is indicative of a temporary increase in concentration for a given VOC. In an example, the concentration of ammonia may increase to 160 ppm within a period of thirty seconds. As the exhaust fan  162  operates to remove airflow containing one or more compounds, the concentration of ammonia may decrease to 100 ppm within the next minute and may remain at that value. The computer system  102  may associate this temporary increase past the second threshold (i.e., 150 ppm) and subsequent decrease to a constant value as an event of tampering with the sensor  108   b  (for example, by spraying an aerosolized compound proximate to the sensor  108   b ). If the determined moving average comprises an average concentration that is greater than the second threshold, the computer system  102  may generate and transmit the alert  118  to the user device  104  indicating that an event associated with a spill of one or more chemicals has occurred within the bathroom  124 . In another example, the concentration of ammonia may steadily increase past a second threshold of 150 ppm. The concentration of ammonia may maintain a value over the second threshold for an amount of time (for example, the rolling window), despite operation of the exhaust fan  162 . The computer system  102  may associate this increase past the second threshold and maintenance above the second threshold as an event associated with a spill of one or more chemicals. 
     In an example, a user may attempt to tamper with the sensor  108   b  by spraying an aerosolized compound proximate to the sensor  108   b.  The user may spray an aerosolized compound proximate to the sensor  108   b  in order to register a false positive that there is a concentration of one or more compounds greater than the first threshold. In this example, the user may attempt to comply with a determined cleaning schedule for the bathroom  124  without performing the actions of cleaning the bathroom  124 . For example, the user may be busy performing other tasks but is aware that the bathroom  124  needs cleaning. A directed spraying of the aerosolized compound towards the sensor  108   b  may overcome the first threshold to signal that the bathroom  124  has been cleaned, but too much of the aerosolized compound may exceed the second threshold. 
     The aerosolized compound may be present within the bathroom  124  for a certain duration of time before the airflow through the exhaust fan  162  may remove the one or more molecules of the aerosolized compound. In this example, the sensor  108   b  may monitor an increase in the concentration of the aerosolized compound by iteratively determining concentration measurements  160 . The computer system  102  may receive a concentration measurement  160  exceeding the second threshold before the one or more molecules of the aerosolized compound are removed from the bathroom  124 . Depending on the duration of time present in the bathroom  124 , the concentration of the aerosolized compound may be insignificant or negligible. The longer the duration of time the aerosolized compound is present in the bathroom  124 , the greater an increase of the moving average of concentration measurements of the aerosolized compound will be. 
     For example, in an event associated with a spill of one or more chemicals occurring in the bathroom  124 , a larger release of one or more compounds may occur when compared to spraying an aerosolized compound. Depending on a variety of factors, such as volume of the liquid of the one or more chemicals spilled, temperature within the bathroom  124 , ventilation, duration of time exposed to the environment within the bathroom, the spilled one or more chemicals may produce one or more compounds at a certain rate. In this example, the rate of production may be greater when the temperature is high, when there is poor ventilation, when there is a large duration of time, or a combination thereof. The computer system  102  may detect an increase in concentration of the produced one or more compounds based on the concentration measurements  160  determined by the sensor  108   b.  As the duration of time wherein the spilled one or more chemicals is exposed may be large, the moving average of the concentration of those produced one or more compounds may increase in relation. 
     For example, a moving average for one or more compounds determined before the spill may be 100 ppm, wherein this may signify that the average concentration of the one or more compounds is 100 ppm for the rolling window. After the spill, the one or more chemicals may not be removed or cleaned by the user wherein during that time period, one or more compounds, such as VOCs, may be produced. A moving average determined after the spill may increase to 151 ppm. If the second threshold is 150 ppm, the computer system  102  may generate and transmit the alert  118  to the user device  104  indicating that an event associated with a spill of one or more chemicals has occurred within the bathroom  124  as the moving average comprises an average concentration greater than 150 ppm. In this example, the alert  118  may prompt an event, such as cleaning spilled one or more chemicals, venting the produced VOCs out through the exhaust fan  162 , or both. 
     In another example, the computer system  102  determines that the user tampered with the sensor  108   b.  In this example, the computer system  102  determines that the moving average comprises an average concentration that is less than the second threshold. The alert  118  generated and transmitted by the computer system  102  may indicate that the sensor  108   b  has been tampered and prompt an event, such as cleaning the bathroom  124  and/or inspecting the sensor  108   b.    
     In a separate example, the user may not have cleaned the bathroom  124  according to the schedule (i.e., once per twelve hours). When the computer system  102  determines that there has not been a cleaning within the schedule, the alert  118  generated and transmitted may indicate that the bathroom  124  was not cleaned within a given period of time and prompt an event, such as cleaning the bathroom  124 . In these examples, the alert  118  may be generated and transmitted via the automatic alerting module  114  of the computer system  102 . 
     As previously described, automatic alerting module  114  represents any suitable set of instructions, logic, or code embodied in a computer-readable storage medium. For example, automatic alerting module  114  may be embodied in memory  110 , a disk, a CD, or a flash drive. In particular embodiments, automatic alerting module  114  may include alerting instructions  142  (e.g., a software application) executable by processor  112  to perform one or more of the functions described herein. In general, automatic alerting module  114  sends alert  118  for display on user device  104  via network  106 . As described, alert  118  is generated by alerting instructions  142  based, at least in part, on the concentration measurements  160  from sensor  108   b  and on threshold values determined via the thresholding module  116 . 
     Thresholding module  116  represents any suitable set of instructions, logic, or code embodied in a computer-readable storage medium. For example, thresholding module  116  may be embodied in memory  110 , a disk, a CD, or a flash drive. In particular embodiments, thresholding module  116  may include thresholding instructions  140  (e.g., a software application) executable by processor  112  to perform one or more of the functions described herein. In general, thresholding instructions  140  determine a first threshold and a second threshold for a period of time. For example, the first threshold represents an event indicating that the bathroom  124  has been cleaned, and the second threshold represents an event indicating either a spill of chemicals in the bathroom or an event of tampering with sensor  108   b.  Each value for first and second thresholds may be any suitable value (for example, 75 ppm, 125 ppm, 150 ppm, etc.). As described above, the first threshold is compared to each received concentration measurements  160 . The second threshold is then compared to each received concentration measurements  160  and to a determined moving average. 
     Example Operation of the System for Diagnostic Analysis of a Toilet Over Time Intervals 
       FIG.  2    is a flow diagram illustrating an example method  200  of the automatic alerting system  100  of  FIG.  1   . In general, method  200  may be utilized by the sensor  108   a,  switch  144 , computer system  102 , and user device  104  of  FIG.  1    to automatically provide the alert  118  for display on user device  104 . The method  200  may begin at operation  202  where the sensor  108   a  (referring to  FIG.  1   ) may be calibrated relative to the toilet tank  122  (referring to  FIG.  1   ). The sensor  108   a  may perform a first distance measurement  126   a  (referring to  FIG.  1   ) to determine a distance from the level of water  120  (referring to  FIG.  1   ) contained in the toilet tank  122  to the sensor  108   a  at an initial water level. The sensor  108   a  may then transmit the first distance measurement  126   a  to the computer system  102  across the network  106  (referring to  FIG.  1   ). The processor  112  (referring to  FIG.  1   ) of the computer system  102  may receive the transmitted first distance measurement  126   a  from the network  106  and may instruct the memory  110  (referring to  FIG.  1   ) to store the first distance measurement  126   a  as the setpoint  128  (referring to  FIG.  1   ). The method  200  may then proceed to both operation  204  and to operation  206  for parallel operations. 
     At operation  204 , the sensor  108   a  may determine a plurality of distance measurements  126  for a period of time (i.e., eight hours). For each distance measurement  126 , the laser diode  130  (referring to  FIG.  1   ) of the sensor  108   a  may produce the laser beam  136  that travels towards the level of water  120 , wherein the laser beam  136  is reflected off of the water  120  to travel back to the sensor  108   a.  The photodetector  132  (referring to  FIG.  1   ) of the sensor  108   a  may receive the reflected laser beam  136 . The sensor processor  134  (referring to  FIG.  1   ) of the sensor  108   a  may determine each distance measurement  126  based on a difference in time between production of the laser beam  136  by the laser diode  130  and reception of the reflected laser beam  136  by the photodetector  132 . The sensor processor  134  may further transmit the plurality of distance measurements  126  across the network  106 . 
     At operation  208 , the processor  112  of the computer system  102  may receive the plurality of distance measurements  126  transmitted over the network  106 . The processor  112  of the computer system  102  may then determine a plurality of instances of a decrease in the level of water  120  (for example, an event associated with flushing the toilet tank  122 ) based on a comparison between each one of the received distance measurements  126  and the setpoint  128 . The method  200  may then proceed to operation  210  and to operation  212  concurrently. 
     At operation  210 , the processor  112  of the computer system  102  may determine whether the determined plurality of instances of the decrease in the level of water  120  is greater than the threshold number stored in the memory  110  for the period of time. If there is a determination that the determined plurality of instances of the decrease in the level of water  120  is greater than the threshold number, the method  200  proceeds to operation  214 . Otherwise, the method  200  proceeds to operation  216 . 
     At operation  214 , the processor  112  of the computer system  102  may transmit the alert  118  across the network  106  to the user device  104 . The alert  118  may indicate that the determined plurality of instances of the decrease in the level of water  120  is greater than the threshold number. Transmission of the alert  118  may signal for an event to occur, such as cleaning the toilet associated with the toilet tank  122 . After transmission of the alert  118 , the method  200  proceeds to end. 
     At operation  216 , the processor  112  of the computer system  102  may determine whether there has been a change in the determined number of the plurality of instances of the decrease in the level of water  120  over a time interval (for example, two hours). If there is a determination that the determined number of the plurality of instances of the decrease in the level of water  120  has not changed over the time interval, the method  200  proceeds to operation  214 . Otherwise, the method  200  proceeds to end. As previously described, the processor  112  of the computer system  102  may transmit the alert  118  across the network  106  to the user device  104  in operation  214 . In this embodiment, transmission of the alert  118  may signal for an event to occur, such as cleaning the toilet and/or performing maintenance on the toilet associated with the toilet tank  122 . After transmission of the alert  118 , the method  200  proceeds to end. 
     Referring back to operation  206 , the switch  144  (referring to  FIG.  1   ) may determine an instance of transition from the closed position to the open position of the pair of contacts  154  (referring to  FIG.  1   ). The pair of contacts  154  may be in a closed position when in proximity to the magnet  158  (referring to  FIG.  1   ) coupled to the door  148  (referring to  FIG.  1   ), wherein the pair of contacts  154  transitions from the closed position to the open position as the door  148  changes from the first position to the second position (for example, by rotating along a side of the door frame  146 ). The switch processor  156  (referring to  FIG.  1   ) may determine an instance of transition from the closed position to the open position and transmit each instance of transition across the network  106 . The processor  112  of the computer system  102  may receive each instance of transition and count each received instance of transition for the pair of contacts within the period of time for storage as the door information  152  (referring to  FIG.  1   ). 
     At operation  212 , the processor  112  of the computer system  102  may determine a ratio of the determined number of the plurality of instances of the decrease in the level of water  120  from operation  208  to a number of instances wherein the door  148  changes from the first position to the second position based on the stored door information  152  from operation  206 . In embodiments, the determined ratio may then be compared to a stored threshold ratio. 
     At operation  218 , the processor  112  of the computer system  102  may determine whether the determined ratio is greater than the stored threshold ratio. If there is a determination that the determined ratio is greater than the stored threshold ratio, the method  200  proceeds to end. Otherwise, the method  200  proceeds back to operation  214 . As previously described, the processor  112  of the computer system  102  may transmit the alert  118  across the network  106  to the user device  104  in operation  214 . In this embodiment, transmission of the alert  118  may signal for an event to occur, such as cleaning the toilet associated with the toilet tank  122  and/or the bathroom  124 . After transmission of the alert  118 , the method  200  proceeds to end. 
     Example Operation of the System for Determining an Ambient Concentration of Compositions for Bathroom Cleaning 
       FIG.  3    is a flow diagram illustrating an example method  300  of the automatic alerting system  100  of  FIG.  1   . In general, method  300  may be utilized by the sensor  108   b,  computer system  102 , and user device  104  of  FIG.  1    to automatically provide the alert  118  for display on user device  104 . The method  300  may begin at operation  302  where the sensor  108   b  (referring to  FIG.  1   ) may be determine a concentration measurement  160  for one or more compounds, such as VOCs, present in the airflow for a period of time. The light source  164  (referring to  FIG.  1   ) may produce a light (for example, ultraviolet light) configured to ionize one or more molecules of the VOC present in the airflow. The pair of electrodes  166  (referring to  FIG.  1   ) may receive the ionized one or more molecules and generate an electrical current proportional to a concentration of the received, ionized one or more molecules. The sensor processor  168  (referring to  FIG.  1   ) may determine a concentration measurement  160  for the VOC based at least in part upon the electrical current generated by the pair of electrodes  166 . The sensor processor  168  may further transmit the concentration measurement  160  across the network  106 . 
     At operation  304 , the processor  112  (referring to  FIG.  1   ) of the computer system  102  may receive the concentration measurement  160  transmitted over the network  106 . 
     The processor  112  of the computer system  102  may then determine whether the received concentration measurement  160  is greater than or equal to a first threshold stored in the memory  110  (referring to  FIG.  1   ) during the period of time. The first threshold is indicative of an event associated with cleaning the bathroom  124  (referring to  FIG.  1   ). If the received concentration measurement  160  is greater than or equal to the first threshold, the computer system  102  determines that a user has cleaned the bathroom  124 . If there is a determination that the received concentration measurement  160  is greater than or equal to the first threshold, the method  300  proceeds to operation  306 . Otherwise, the method  300  proceeds to operation  308 . 
     At operation  308 , the processor  112  of the computer system  102  may determine whether the system  100  is operating within a first period of time. For example, an entity managing the bathroom  124  may monitor cleaning of the bathroom  124  through a schedule (i.e., once per twelve hours). In this example, the first period of time may be a twelve-hour shift from 8 AM to 8 PM. During operation  308 , the computer system  102  may determine if the system  100  is still operating within the twelve-hour shift or past the twelve-hour shift (i.e., past 8:01 PM). If there is a determination that the system  100  is operating within the first period of time, the method  300  proceeds to back to operation  302 . The system  100  may repeat operation  302 , operation  304 , and operation  308  to iteratively determine concentration measurements  160  and compare the determined concentration measurements  160  to the first threshold while operating within the first period of time. For example, the computer system  102  may continue to monitor the concentration of VOCs either until the first threshold is exceeded (potentially indicating that the bathroom has been cleaned) or until the twelve-hour shift has ended. Otherwise, the method  300  proceeds to operation  310 . 
     At operation  310 , the processor  112  of the computer system  102  may transmit the alert  118  across the network  106  to the user device  104 . In this example, the period of time in which the entity was to clean the bathroom  124  has passed (i.e., based on the cleaning schedule). The bathroom  124  may have required a cleaning once every twelve hours. After the end of the twelfth hour, if there was no determined cleaning based on a comparison between the received concentration measurement  160  and the first threshold, the computer system  102  generates the alert  118 . The alert  118  may indicate that the bathroom  124  was not cleaned within a given period of time (i.e., the first period of time). Transmission of the alert  118  may signal for an event to occur, such as cleaning the bathroom  124 . After transmission of the alert  118 , the method  300  proceeds to end. 
     Referring back to operation  306 , the processor  112  of the computer system  102  may determine whether the received concentration measurement  160  is greater than a second threshold stored in the memory  136 . The second threshold is indicative of further production of VOCs not typical of an event of cleaning the bathroom  124 . Such events may include spilling one or more chemicals in the bathroom  124  or tampering with the sensor  108   b.  If there is a determination that the received concentration measurement  160  is greater than the second threshold, the method  300  proceeds to operation  312 . For example, one received concentration measurement  160  may comprise a value of 149 ppm, and the second threshold may be 150 ppm. Another received concentration measurement  160  may comprise a value of 155 ppm, thereby exceeding the second threshold. The increasing value of concentration measurements  160  indicates further production of VOCs in the bathroom  124  (for example, from a spill or from tampering with the sensor  108   b ). Otherwise, the method  300  proceeds to operation  314 . 
     At operation  314 , the processor  112  of the computer system  102  may determine that the entity managing the bathroom  124  has complied with the cleaning schedule. For example, an employee for the entity may have cleaned the bathroom  124  within the twelve-hour shift. After the cleaning, the processor  112  of the computer system  102  may have determined for the received concentration measurement  160  to comprise a value between the first threshold and the second threshold. The processor  112  may instruct the memory  110  to store an indication that the bathroom  124  was cleaned in response to a determination that the received concentration measurement  160  is greater than the first threshold and less than the second threshold. After storing the indication, the method  300  proceeds to end. 
     Referring back to operation  312 , the processor  112  of the computer system  102  may determine a moving average of an average concentration of one or more compounds present in the airflow over a given time period (for example, 10 minutes). The moving average is representative of the average concentration of one or more compounds within a rolling window of time over the period of time. Determining the moving average may distinguish between individual false positive indications of cleaning the bathroom  124  (i.e., a spill or tampering with the sensor  108   b ). In an example event of a spill, one or more chemicals may continue to produce one or more compounds, such as VOCs, until cleaned and removed from the bathroom  124 . In an example event of tampering with the sensor  108   b,  an employee associated with the entity may continue to produce one or more VOCs by spraying an aerosolized compound towards the sensor  108  for a period of time. 
     At operation  316 , the processor  112  of the computer system  102  may then compare the determined moving average to the second threshold to determine whether the determined moving average comprises an average concentration that is greater than the second threshold. The determined moving average being less than the second threshold is indicative of a temporary increase in concentration for a given VOC. In an example, the concentration of ammonia may increase to 160 ppm within a period of thirty seconds. As the exhaust fan  162  operates to remove airflow containing one or more compounds, the concentration of ammonia may decrease to 100 ppm within the next minute and may remain at that value. The computer system  102  may associate this temporary increase past the second threshold (i.e., 150 ppm) and subsequent decrease to a constant value as an event of tampering with the sensor  108   b  (for example, by spraying an aerosolized compound proximate to the sensor  108   b ). If there is a determination that the determined moving average is greater than the second threshold, the method  300  proceeds to operation  318 . In another example, the concentration of ammonia may steadily increase past a second threshold of 150 ppm. The concentration of ammonia may maintain a value over the second threshold for an amount of time, despite operation of the exhaust fan  162 . The computer system  102  may associate this increase past the second threshold and maintenance above the second threshold as an event associated with a spill of one or more chemicals. Otherwise, the method  300  proceeds to operation  320 . 
     At both operation  318  and operation  320 , the processor  112  of the computer system  102  may transmit the alert  118  across the network  106  to the user device  104 . With reference to operation  318 , the alert  118  may indicate that an event associated with a spill of one or more chemicals has occurred within the bathroom  124 . Transmission of the alert  118  may signal for an event to occur, such as cleaning or removing the spill in the bathroom  124 . With reference to operation  320 , the alert  118  may indicate that the sensor  108  has been tampered. Transmission of the alert  118  may signal for an event to occur, such as inspecting the sensor  108   b.  After transmission of the alert  118 , the method  300  proceeds to end. 
     Modifications, additions, or omissions may be made to the methods described herein without departing from the scope of the disclosure. The methods may include more, fewer, or other steps. Additionally, steps may be performed in any suitable order. That is, the steps of any method disclosed herein do not have to be performed in the exact order disclosed, unless explicitly stated. 
     As used in this document, “each” refers to each member of a set or each member of a subset of a set. Furthermore, as used in the document “or” is not necessarily exclusive and, unless expressly indicated otherwise, can be inclusive in certain embodiments and can be understood to mean “and/or.” Similarly, as used in this document “and” is not necessarily inclusive and, unless expressly indicated otherwise, can be inclusive in certain embodiments and can be understood to mean “and/or.” All references to “a/an/the element, apparatus, component, means, step, etc.” are to be interpreted openly as referring to at least one instance of the element, apparatus, component, means, step, etc., unless explicitly stated otherwise. 
     Furthermore, reference to an apparatus or system or a component of an apparatus or system being adapted to, arranged to, capable of, configured to, enabled to, operable to, or operative to perform a particular function encompasses that apparatus, system, component, whether or not it or that particular function is activated, turned on, or unlocked, as long as that apparatus, system, or component is so adapted, arranged, capable, configured, enabled, operable, or operative. 
     The embodiments disclosed herein are only examples, and the scope of this disclosure is not limited to them. Particular embodiments may include all, some, or none of the components, elements, features, functions, operations, or steps of the embodiments disclosed herein. Certain embodiments are in particular disclosed in the attached claims directed to a method, a storage medium, a system and a computer program product, wherein any feature mentioned in one claim category, e.g. method, can be claimed in another claim category, e.g. system, as well. The dependencies or references back in the attached claims are chosen for formal reasons only. However, any subject matter resulting from a deliberate reference back to any previous claims (in particular multiple dependencies) can be claimed as well, so that any combination of claims and the features thereof are disclosed and can be claimed regardless of the dependencies chosen in the attached claims. The subject-matter which can be claimed comprises not only the combinations of features as set out in the attached claims but also any other combination of features in the claims, wherein each feature mentioned in the claims can be combined with any other feature or combination of other features in the claims. Furthermore, any of the embodiments and features described or depicted herein can be claimed in a separate claim and/or in any combination with any embodiment or feature described or depicted herein or with any of the features of the attached claims.