Gas detection with acoustic sensor

Abstract

A gas concentration determination system includes an acoustic sensor that generates acoustic sensor data and a humidity sensor that generates relative humidity data. The modified relative humidity is determined based at least in part on the acoustic sensor data and the relative humidity data. The gas concentration is determined using the modified relative humidity and acoustic data. For example, using the modified relative humidity rather than the relative humidity data may reduce false alarms when detecting gas leaks in the HVAC system.

Description

[0001] CROSS-REFERENCE TO RELATED APPLICATIONS

[0002] This application claims the benefit of priority to U.S. Provisional Patent Application No. 63 / 593,751, “Gas Detection Using Acoustic Sensors,” filed on October 27, 2024, the entire contents of which are incorporated herein by reference. Technical Field

[0003] The subject disclosure relates to sensing systems and, more particularly, to improved systems for determining relative humidity using sonic velocity sensing elements. Technical Background

[0004] HVAC systems have recently begun using more environmentally friendly refrigerants. These refrigerants are better for the environment, but can still have adverse effects if not handled properly. For example, some refrigerants can be very flammable. Therefore, detecting and / or mitigating leaks in HVAC systems that use these and / or other refrigerants can be very important. BRIEF DESCRIPTION OF THE DRAWINGS

[0005] In order to make it easier for a person having ordinary skill in the art to which the disclosed systems and techniques relate to understand how to make and use these systems and techniques, reference is made to the following drawings.

[0006] Figure 1 is a schematic diagram of a gas detection and mitigation system in accordance with aspects of the present disclosure.

[0007] Figure 2 is a flow chart showing a line graph of relative humidity values ​​obtained using two techniques in accordance with aspects of the present disclosure.

[0008] Figure 3 is a flow chart illustrating an example process for detecting gas concentration in a gas sample in accordance with aspects of the present disclosure. DETAILED DESCRIPTION

[0009] The subject technology overcomes prior art problems associated with relative humidity sensing elements and gas detection systems using such elements. For example, the systems and techniques described herein can provide improved sensing elements and systems that can be used in countless different systems, including many different heating, ventilation, and cooling (HVAC) systems. For example, the technology described herein provides a sensing system that can minimize erroneous relative humidity readings, especially during rapid humidity changes. For example, the sensing system described herein can reduce false alarms. The following detailed description of certain preferred embodiments in conjunction with the accompanying drawings will make it easier for those of ordinary skill in the art to understand the advantages and other features of the systems and methods disclosed herein, and representative embodiments of the present disclosure are listed in the accompanying drawings.

[0010] Some conventional gas detection sensors include a speed of sound (SOS) sensing element (e.g., an acoustic sensor) to measure the speed of sound of a gas sample in a sensing cavity. The measurement can be used with inputs from temperature and humidity sensors (measuring variables temperature and humidity, respectively) to indicate the concentration of the gas (as an unknown variable) within the gas detection cavity. In some embodiments, the relative humidity measurement, the temperature measurement, and the speed of sound measurement can be input into a second-order polynomial model to calculate the corresponding gas concentration.

[0011] In certain aspects of the present disclosure, improved techniques may be used to detect the relative humidity of a target gas (such as a coolant, refrigerant, or the like) using a velocity of sound sensing element. Some example techniques according to the present disclosure may include fixing the known gas concentration to that of ordinary air. The sensing signal may provide a fast response relative humidity sensor that does not rely on the absorption / desorption characteristics of bulk materials used in typical relative humidity sensing. Due to the relationship between the velocity of sound and relative humidity, sensors according to the present disclosure may be particularly effective in high temperature and / or high relative humidity ranges where conventional relative humidity sensors may lose measurement capabilities.

[0012] Aspects of the present disclosure may also include changing the input of an onboard relative humidity sensor, such as using a dynamic deterministic algorithm. For example, the algorithm may use sensor inputs (such as measured relative humidity, measured temperature levels, measured rates of change of the natural frequency of a speed of sound sensing element, and / or rates of change of a standard relative humidity sensor) to determine or identify rapid relative humidity conversions. In various embodiments, the algorithm may calculate a relative humidity value (e.g., a calculated relative humidity value) based on the measured speed of sound, and may correspondingly modify the measured relative humidity value (e.g., the measured relative humidity value) from the relative humidity sensor. In certain embodiments, in order to reduce overcompensation, the measured relative humidity value and the calculated relative humidity value may be combined, for example, using a weighted average. In various embodiments, the weighted average may be based at least in part on the rate of change of the measured relative humidity value at the relative humidity sensor, for example, proportional thereto.

[0013] In certain aspects of the present disclosure, the improved techniques described herein can allow a gas sensor based on the velocity of sound to respond appropriately to situations of rapid humidity changes by not causing erroneous readings, which may be caused, for example, by a mismatch in the time constant between the velocity of sound signal and the relative humidity sensor.

[0014] As a result of the improved relative humidity sensors described herein, false alarms associated with rapid changes in relative humidity may be reduced, thereby reducing or avoiding the need for inspection and repair of non-events.These and other features and advantages of the present disclosure will be discussed with reference to the drawings.

[0015] Figure 1 1 is a schematic diagram of a gas detection and mitigation system 100. In various embodiments, the gas detection and mitigation system 100 generally includes a gas detection sensing system 102 and a gas mitigation system 104. In certain embodiments, the gas detection and mitigation system 100 may be used in conjunction with a heating, ventilation, and air conditioning (HVAC) system. Without limitation, the HVAC system that may be used with the gas detection and mitigation system 100 may be a vehicle HVAC system, a commercial HVAC system, a residential HVAC system, and / or any other HVAC system that uses a refrigerant or other material that may be detected in accordance with the systems and techniques described herein. In certain embodiments, the refrigerants used in the HVAC system may be hazardous, flammable, and / or unsafe. Therefore, a system such as the gas detection and mitigation system 100 may be used to mitigate any such unsafe conditions associated with a malfunction, failure, damage, or other undesirable condition of the HVAC system.

[0016] In general, the gas detection sensing system 102 can be configured to detect the presence and / or amount of gas, refrigerant, and / or other substances in an HVAC system. In some embodiments, the gas detection sensing system 102 can be configured to determine the presence of refrigerant (e.g., refrigerant leaking from a closed HVAC system). The gas detection sensing system 102 can also include functionality to generate and / or transmit a signal, command, or the like associated with an event based on the detection.

[0017] The gas mitigation system 104 can be configured to receive signals / commands from the gas detection sensing system 102 and take some action to mitigate the event signaled by the gas detection sensing system 102. Without limitation, the gas mitigation system 104 can include a fan or other device that increases the circulation of air or other fluid around the gas detection sensing system 102, for example, to disperse leaking refrigerant or other gas. In other embodiments, the gas mitigation system can include functionality to generate, transmit, and / or output an alarm associated with the presence of gas. For example, the gas mitigation system 104 can include an audible alarm and / or a visual alarm in the vicinity of the gas detection and mitigation system. In other embodiments, the gas mitigation system can generate an alarm and transmit the alarm (e.g., via a wireless protocol) to a computing device associated with the HVAC system. For example, the alarm can be transmitted to a computing device associated with a technician, manufacturer, installer, homeowner, vehicle owner, and / or other person or computing system.

[0018] like Figure 1As shown, the gas detection sensor system 102 includes a sound velocity sensing element 106, a humidity sensing element 108, a temperature sensing element 110, a relative humidity modification calculation component 112, and / or a gas concentration determination component 114. Although the various sensing elements and components are schematically shown as separate but related components, Figure 1 For example, but not limited to, the relative humidity modification calculation component 112 and the gas concentration determination component 114 may be formed as a single unit, and / or the functions of these components may be performed by a single processor or other computing device. Figure 1 are schematic diagrams and are intended only to show example configurations and are generally arranged for ease of explanation.

[0019] The speed of sound (SOS) sensing element 106 may be configured to measure or determine the speed of sound of a gas sample in a sensing resonant cavity. For example, the speed of sound sensing element 106 may determine the presence of a gas (e.g., a refrigerant) based on a change in the speed of sound measurement in the cavity. Figure 1 As shown, the sound velocity sensing element 106 generates sound velocity data 116. The sound velocity data 116 may be sound velocity measurements generated during use of the gas detection and mitigation system 100, a frequency signal associated with oscillations of the sound velocity sensing element 106, acoustic sensor data, and / or other associated data and / or metadata. The sound velocity data 116 may be generated at a predetermined frequency or time constant, and the sound velocity data 116 may include associated timing data, such as a timestamp or the like. In one embodiment, the sound velocity sensor may be an acoustic sensor, such as those described in U.S. Patent No. 9,869,659, issued on January 16, 2018, entitled “Acoustic Sensor,” the entire contents of which are incorporated herein by reference.

[0020] The humidity sensing element 108 may be configured to sense humidity associated with the external environment, such as relative humidity. For example, the humidity sensing element 108 may be positioned and / or otherwise configured to determine the relative humidity of the environment in which the sound velocity sensing element 106 is located. Figure 1 As shown, the humidity sensing element 108 generates measured relative humidity data 118, for example, as RH measDisplay. The measured relative humidity data 118 can be a relative humidity generated at a predetermined frequency or time constant. In various embodiments, the frequency or time constant associated with generating the measured relative humidity data 118 can be different from the frequency or time constant associated with generating the sound speed data 116 discussed above. In other embodiments, the measured relative humidity data 118 can be generated at a different phase (e.g., at a different time) than the sound speed data 116. In various embodiments, the humidity sensing element 108 can be an onboard surface mount technology (SMT) relative humidity sensor. Therefore, for example, in certain embodiments of the present disclosure, the sound speed sensing element 106 and the humidity sensing element 108 can be disposed on the same substrate or board (e.g., a circuit board).

[0021] like Figure 1 As shown, the gas detection sensor system 102 may further include a temperature sensor 110. In various embodiments, the temperature sensor 110 may be configured to output temperature data 120, which may include a temperature value associated with the environment in which the acoustic velocity sensing element 106 and / or the humidity sensing element 108 is located. In various embodiments, the temperature sensor 110 may include a thermocouple, a thermistor, a resistance thermometer, a silicon bandgap temperature sensor, an infrared thermometer, or the like, but is not limited thereto.

[0022] In some conventional gas detection systems, the velocity of sound data 116, the relative humidity data 118, and / or the temperature data 120 may be used to determine the presence / concentration of a gas (e.g., a refrigerant). For example, conventional techniques may include inputting the velocity of sound data 116, the relative humidity data 118, and the temperature data 120 into a second-order polynomial model to calculate the corresponding gas concentration. However, certain embodiments of such conventional processing methods may result in false alarms, such as erroneous "detections" of refrigerants. Such false alarms may be caused by a mismatch in time constants associated with the velocity of sound data 116 and the relative humidity data 118. For example, when the relative humidity in the HVAC system drops rapidly, such as when the HVAC system is turned on under hot and / or humid conditions, the conventional system may erroneously "detect" a refrigerant leak, such as because the relative humidity data 118 is delayed relative to the velocity of sound data 116 and / or vice versa. Such erroneous readings may result in unnecessary mitigation efforts, including, but not limited to, alarms, alerts, maintenance, system shutdowns, and / or the like.

[0023] In various aspects of the present disclosure, the relative humidity modification calculation component 112 determines and / or generates modified relative humidity data 122. For example, Figure 1As shown, the relative humidity modification calculation component 112 is configured to receive the sound speed data 116 and the measured relative humidity data 118 and output the modified relative humidity data 122. In various embodiments, the relative humidity modification calculation component 112 may include processing, for example, including an algorithm or the like, to modify the measured relative humidity data 118 based at least in part on the sound speed data 116. Without limitation, the relative humidity modification calculation component 112 can calculate the relative humidity value and the relationship between the relative humidity and the molar mass based on the sound speed data 116 (e.g., through the gas sample). The calculated relative humidity can be used to determine the modified relative humidity, for example, based on both the relative humidity data 118 and the calculated relative humidity data, which is determined based on the sound speed data 116. This modification can correct the mismatch of the time constant between the sound speed sensing element 106 and the humidity sensing element 108.

[0024] In some embodiments, the relative humidity modification calculation component 112 may include a dynamic deterministic algorithm to generate the modified relative humidity data 122. For example, the relative humidity modification calculation component may determine the modified relative humidity data 122 based at least in part on the measured relative humidity data 118, the temperature data 120 (which may be selectively received from the temperature sensing element 110), the measured rate of change of the natural frequency of the speed of sound sensing element (e.g., from the speed of sound data 116), and / or the rate of change of the measured relative humidity data 118. For example, such data may be used to determine a rapid relative humidity transition. The relative humidity modification calculation component 112 may calculate a relative humidity value based on the measured speed of sound, and appropriately modify the measured relative humidity data based on the calculated relative humidity value. In some embodiments, for example, to reduce overcompensation, the relative humidity measured value (e.g., from the measured relative humidity data 118) and the relative humidity calculated by the relative humidity modification calculation component 112 based on the measured speed of sound may be combined into the modified relative humidity data 122. For example, the modified relative humidity data 122 may include a weighted average of measured and calculated relative humidity values. For example, the weighted average may be proportional to, or otherwise based at least in part on, the rate of change of the humidity sensing element 108. In certain embodiments, the modified relative humidity data 122 may match the time constant of the humidity sensor to the frequency output of the sensing element to avoid false increases in gas concentration readings caused by rapid drops in relative humidity, such as seen in certain HVAC applications detailed herein. In certain embodiments, the relative humidity modification calculation component 112 may include implementing an algorithm for calculating relative humidity using a speed of sound value, combined with deterministic use limits to allow the sensor to avoid false positive readings.

[0025] The gas concentration determination component 114 may include functionality to determine whether (and / or how much) gas is present in the environment of the gas detection sensor system 102. Figure 1 In an embodiment of the present invention, the gas concentration determination component 114 can receive the sound speed data 116, the modified relative humidity data 122, and the temperature data 120. For example, the gas concentration determination component 114 can include functionality to implement one or more models (e.g., a second-order polynomial model) to determine the gas concentration data 124. For example, the gas concentration data 124 can be a binary determination (e.g., gas present / gas not present). In other embodiments, the gas concentration data can include quantitative data, such as a percentage of a gas, a measured amount of a gas, or the like.

[0026] Without limitation, the gas concentration determination component 114 can be configured to determine the gas concentration using one or more formulas. For example, the speed of sound in the gas can be expressed by Formula 1:

[0027]

[0028] Wherein, v is the speed of sound (e.g., from the speed of sound data 116), R is the gas constant, T is the temperature (e.g., from the temperature data 120), and M is the molar mass of the gas. Also in various embodiments, the gas molar mass M can be represented by Formula 2:

[0029] M=f(T,P,ρ) (Formula 2)

[0030] Where p is the density of the gas. Thus, given the speed of sound through the gas sample (e.g., from the speed of sound data 116) and the relationship between relative humidity and molar mass, the relative humidity can be determined. As described above, the calculated or determined relative humidity can be used to modify the relative humidity data 118 from the humidity sensing element 108. A more accurate determination of the gas concentration can then be determined using the modified relative humidity data 122.

[0031] exist Figure 1 In some embodiments, the gas mitigation system 104 may include functionality to determine whether and / or what action should be taken to mitigate a potential condition based on the gas concentration data 124. In other embodiments, the gas detection sensing system 102 may include functionality to receive and analyze the gas concentration data 124. In these embodiments, the gas detection sensing system 102 may further include functionality to generate and / or transmit alarms, instructions, commands, and / or the like to cause the gas mitigation system 104 to take certain actions.

[0032] In various embodiments, the various illustrated blocks and / or other aspects of the systems and components described and detailed herein may be implemented in an intelligent hardware device, such as a central processing unit (CPU), a microcontroller, an application specific integrated circuit (ASIC), or may be implemented as part of a reconfigurable device. Aspects of the systems and components described herein may include random access memory (RAM) and read-only memory (ROM), which may include instructions that are configured to, when executed (or when compiled and executed), cause aspects of the systems and / or components discussed herein to perform various functions described herein (including but not limited to Figure 3 The various components of the system may be implemented using one or more independent CPUs or ASICs. In addition, these components may be implemented using one or more ASICs, either individually or collectively, to perform some or all of the applicable functions in hardware. Each of the components noted may be a means of performing one or more functions associated with the operation of the system.

[0033] In some embodiments of the present disclosure, the gas detection sensor system 102 can be embodied as a single device, for example, for direct placement in an environment to detect gas in the environment. For example, the gas detection sensor system 102 can include a housing that supports one or more operating components, such as a sound velocity sensing element 106, a humidity sensing element 108, a temperature sensing element 110, a relative humidity modification calculation component 112, and / or a gas concentration determination component 114. Also in various embodiments, the sound velocity sensing element 106, the humidity sensing element 108, the temperature sensing element 110, the relative humidity modification calculation component 112, and / or the gas concentration determination component 114 can be disposed on one or more substrates (e.g., one or more circuit boards or the like) and / or connected via the one or more substrates. For example, but not limited to, the sound velocity sensing element 106, the humidity sensing element 108, and the temperature sensing element 110 can be mounted on a circuit board, and the relative humidity modification calculation component 112 and the gas concentration determination component 114 can be implemented by a processing component (e.g., an ASIC, a CPU, and / or the like).

[0034] Figure 2 2 is a line graph 200 showing relative humidity measurements over time. A first line 202 shows the relative humidity calculated using the sound velocity data as described herein. A second line 204 shows the relative humidity measured by a sensor, such as the humidity sensing element 108. As shown, there are differences between the measurements of relative humidity. For example, line 204 shows the lag of detecting a drop in relative humidity using only the sensor relative to the value calculated using the sound velocity data.

[0035] When using relative humidity to determine gas concentrations, the difference between the calculated relative humidity and the actual relative humidity can result in variations. More specifically, this difference can result in different calculated gas concentrations, and in some cases this difference can be large enough to falsely generate an alarm. For example, certain applications, such as air conditioning applications, may experience rapid changes in relative humidity. However, conventional relative humidity sensors may be slow to detect such rapid changes, and as a result, gas concentrations may be artificially inflated, causing the system to trip. Figure 2 As shown, line 204 corresponding to relative humidity sensor measurements detects a slower rate of decrease in relative humidity compared to the relative humidity values ​​calculated according to aspects of the present disclosure (shown by line 202 ).

[0036] Figure 3 An example process 300 is shown in accordance with various aspects of the present disclosure. The process is illustrated in the form of a logical process diagram, in which each operation represents a sequence of operations that can be implemented by software, hardware, or a combination thereof. In terms of software, the operations represent computer-executable instructions stored on one or more computer-readable storage media, which, when executed by one or more processors, perform the stated operations. Generally speaking, computer-executable instructions include routines, programs, objects, components, data structures, etc. that perform specific functions or implement specific abstract data types. The order in which the operations are described is not meant to be limiting, and any number of the described operations may be combined in any order and / or in parallel to implement the process.

[0037] Various illustrative operations, components, and systems related to the content disclosed herein can be implemented or perform the functions described herein by a general-purpose processor, a digital signal processor (DSP), an application-specific integrated circuit (ASIC), a field-programmable gate array (FPGA) or other programmable logic device, discrete gate or transistor logic, discrete hardware components, or any combination thereof. A general-purpose processor can be a microprocessor, but can also be any conventional processor, controller, microcontroller, or state machine. The processor can also be implemented as a combination of computing devices, for example, a combination of a DSP and a microprocessor, multiple microprocessors, one or more microprocessors combined with a DSP core, or any other such configuration.

[0038] In more detail, Figure 3 is a flow chart showing an example process 300 for determining a gas concentration of a gas sample. In various embodiments, aspects of the process 300 may be described above with reference to Figure 1 The process 300 may be performed by the gas detection sensor system 102 and / or the gas mitigation system 104 discussed above. However, the process 300 is not limited to being performed by Figure 1 system to execute, Figure 1 The system is also not limited to performing process 300.

[0039] At operation 302, process 300 includes receiving relative humidity data including relative humidity measurements of a gas sample from a relative humidity sensor. In various embodiments, the relative humidity sensor may be an onboard humidity sensor.

[0040] At operation 304, process 300 includes receiving sound velocity data associated with the gas sample from a sound velocity sensor. The sound velocity sensor may be the sound velocity sensing element 106 discussed above.

[0041] At operation 306, process 300 includes determining a modified relative humidity value for the gas sample based on the relative humidity measurement and the sound velocity data. As described above, the time constants of the sound velocity sensing element 106 and the humidity sensing element 108 may not match. The modified relative humidity value can account for this mismatch. For example, the modified relative humidity value can be based at least in part on a calculated relative humidity value that is based at least in part on the sound velocity value and determined by fixing the known gas concentration to the normal air concentration. In this way, a fast-response relative humidity measurement that is independent of the absorption / desorption characteristics of the bulk material can be determined. In various embodiments, operation 306 can be performed by the relative humidity modification calculation component 112 discussed above.

[0042] In an embodiment of the present disclosure, operation 306 may be performed in response to determining a relative humidity transition. As described above, aspects of the present disclosure may be particularly useful for compensating for rapid humidity transitions, such as in an air conditioning system in a high temperature environment. Figure 2 As described above, conventional relative humidity sensors may be slow to detect humidity changes, resulting in incorrect gas concentration readings. Therefore, process 300 may include, for example, as part of or prior to operation 306, determining that a rapid relative humidity transition has occurred. For example, a rapid change may be determined based at least in part on a rate of change of a measured natural frequency of a sound velocity sensor (acoustic sensor) and / or a rate of change of a humidity sensing element.

[0043] At operation 308, process 300 includes optionally receiving temperature data associated with the gas sample from a temperature sensor. In various embodiments, the temperature data may be received prior to operation 306, and the modified relative humidity value may be selectively determined based at least in part on the temperature data.

[0044] At operation 310, process 300 includes determining a gas concentration of the gas sample based on the sound velocity data, the modified relative humidity value, and / or the temperature data. For example, operation 310 may be performed by gas concentration determination component 114 described in detail above.

[0045] As described above, aspects of the present disclosure may also improve the detection of unsafe gases and / or reduce false positive detections of unsafe gases in HVAC systems and / or other refrigeration systems. For example, as with conventional systems, aspects of the present disclosure may detect unsafe conditions, but may also reduce the number of inaccurate detections caused by sudden changes in environmental conditions (such as temperature and / or humidity). Without limitation, sensors using the systems and techniques described herein may be used in many different environments and / or many different systems. For example, the techniques and systems described herein may be used in commercial, residential, and / or other air conditioning systems. In addition, the systems and techniques described herein may also be used in commercial, residential, and / or other refrigeration systems. As described in detail herein, aspects of the present disclosure may be particularly useful in detecting gases used as refrigerants.

[0046] Although the subject technology has been described with respect to preferred embodiments, it will be readily appreciated by those skilled in the art that various changes and / or modifications may be made to the subject technology without departing from the spirit or scope of the subject technology. For example, each claim may be subordinate to any or all claims in a multiple-dependency manner, even if such a claim was not initially proposed.

Claims

1. A method for determining gas concentration, the method comprising: receiving a measured relative humidity of the gas sample from a humidity sensor; receiving acoustic sensor data associated with the gas sample from the acoustic sensor; determining a calculated relative humidity of the gas sample based at least in part on the acoustic sensor data; as well as A concentration of the gas in the gas sample is determined based at least in part on the measured relative humidity and the calculated relative humidity. 2 . The method of claim 1 , wherein determining the calculated relative humidity is based at least in part on a known concentration of a gas in the ambient air.

3. The method according to claim 1, further comprising: modifying the measured relative humidity based at least in part on the calculated relative humidity to determine a modified relative humidity, Wherein determining the gas concentration is based at least in part on the modified relative humidity.

4. The method according to claim 3, further comprising: A relative humidity conversion is determined, wherein modifying the measured relative humidity is based at least in part on the relative humidity conversion.

5. The method of claim 4, wherein the acoustic sensor data is sound velocity data, the method further comprising: determining a rate of change of a measured natural frequency of the sound velocity data based at least in part on the sound velocity data; as well as A relative humidity transition is determined based at least in part on the measured rate of change of the natural frequency.

6. The method according to claim 4, further comprising: Determine the measured relative humidity conversion rate, A relative humidity conversion is determined based at least in part on the measured relative humidity conversion rate. 7 . The method of claim 3 , wherein determining the modified relative humidity comprises determining a weighted average based on the measured relative humidity and the calculated relative humidity.

8. The method of claim 7, wherein the weighted average is proportional to the measured relative humidity conversion rate.

9. The method according to claim 1, further comprising: Receive the temperature of the gas sample from the temperature sensor, Wherein determining the concentration of the gas in the gas sample is based at least in part on the temperature.

10. The method of claim 1, wherein the gas concentration is a concentration of a refrigerant.

11. A gas detection sensor, comprising: a humidity sensor that generates relative humidity data associated with the gas sample; an acoustic sensor configured to generate sound velocity data associated with the gas sample; processor; as well as A memory storing instructions executable by a processor to perform the following operations, including: receiving a measured relative humidity of the gas sample from a humidity sensor; receiving sound velocity data associated with the gas sample from an acoustic sensor; determining a calculated relative humidity of the gas sample based at least in part on the speed of sound data; and A concentration of the gas in the gas sample is determined based at least in part on the measured relative humidity and the calculated relative humidity.

12. The gas detection sensor according to claim 11, further comprising: The gas mitigation system, said operation further comprising: determining that a concentration of the gas equals or exceeds a threshold concentration of the gas; and Causes the gas mitigation system to take action to mitigate the presence of gas.

13. The gas detection sensor of claim 12, wherein causing the gas mitigation system to take action comprises causing the gas mitigation system to at least one of sound an alarm or increase air flow.

14. The gas detection sensor according to claim 11, further comprising: a temperature sensor configured to generate temperature data associated with the gas sample, Wherein determining the concentration of the gas in the gas sample is based at least in part on the temperature data.

15. The gas detection sensor of claim 11, the operations further comprising: modifying relative humidity data received from the humidity sensor based at least in part on the calculated relative humidity to determine a modified relative humidity, Wherein determining the gas concentration is based at least in part on the modified relative humidity.

16. The gas detection sensor of claim 15, the operations further comprising: A relative humidity conversion is determined, wherein modifying the measured relative humidity is based at least in part on the relative humidity conversion.

17. The gas detection sensor of claim 16, the operations further comprising: determining the rate of change of the measured natural frequency of the sound velocity data; as well as A relative humidity transition is determined based at least in part on the measured rate of change of the natural frequency.

18. The gas detection sensor according to claim 16, further comprising: Determine the rate of change of relative humidity data, A relative humidity transition is determined based at least in part on a rate of change of the relative humidity data.

19. The gas detection sensor of claim 16, wherein determining the modified relative humidity comprises determining a weighted average based on relative humidity data received from the humidity sensor and the calculated relative humidity.

20. The gas detection sensor of claim 19, wherein the weighted average is proportional to the rate of change of the relative humidity data received from the humidity sensor.

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