Hybrid sensor method

Abstract

A method of determining a presence, concentration or change in concentration of a first or second material in an environment is disclosed. The method comprises measuring a response of a first sensor to the first and second material, wherein the first sensor is one of a metal oxide sensor, an electrochemical sensor, a photoionisation sensor, an infrared sensor, a pellistor sensor, an optical particle monitor, a quartz crystal microbalance sensor, a surface acoustic wave sensor, a cavity ring-down spectroscopy sensor, or a biosensor. The method further comprises measuring a response of a second sensor to the first and second material, wherein the second sensor is another one of a metal oxide sensor, an electrochemical sensor, a photoionisation sensor, an infrared sensor, a pellistor sensor, an optical particle monitor, a quartz crystal microbalance sensor, a surface acoustic wave sensor, a cavity ring-down spectroscopy sensor, a biosensor or a field effect transistor sensor. The method further comprises determining from first and second sensor measurements, a presence, concentration or change in concentration of the first or second material.

1 . A method of determining a presence, concentration or change in concentration of a first or second material in an environment, the method comprising:
 measuring a response of a first sensor to the first and second material, wherein the first sensor is one of a metal oxide sensor, an electrochemical sensor, a photoionisation sensor, an infrared sensor a pellistor sensor, an optical particle monitor, a quartz crystal microbalance sensor, a surface acoustic wave sensor, a cavity ring-down spectroscopy sensor or a biosensor;   measuring a response of a second sensor to the first and second material, wherein the second sensor is a another one of a metal oxide sensor, an electrochemical sensor, a photoionisation sensor, an infrared sensor or a pellistor sensor, an optical particle monitor, a quartz crystal microbalance sensor, a surface acoustic wave sensor, a cavity ring-down spectroscopy sensor, a biosensor or a field effect transistor sensor;   determining from first and second sensor measurements, a presence, concentration or change in concentration of the first or second material.   
     
     
         2 . The method of  claim 1  wherein the first or second material has been removed from the environment. 
     
     
         3 . The method of  claim 1  further comprising applying a correction to the first sensor measurement of the first or second material based on the second sensor measurement of the same material. 
     
     
         4 . The method of  claim 1  further comprising applying a correction to the second sensor measurement of the first or second material based on the first sensor measurement of the same material. 
     
     
         5 . The method of  claim 1  wherein the environment is a gaseous environment and gas drawn from the environment is desiccated and the response of the first and/or second sensors is a response to the desiccated gas. 
     
     
         6 . The method of  claim 5  wherein the desiccated gas is hydrated after desiccation and the response of the first and/or second sensors is a response to the hydrated gas. 
     
     
         7 . The method of  claim 1  wherein in response to determining that the first material is below a threshold, the first material concentration in the environment is increased. 
     
     
         8 . The method of  claim 1  wherein the first material is 1-methylcyclopropene. 
     
     
         9 . The method of  claim 1  wherein the second material is ethylene. 
     
     
         10 . A system comprising:
 a processor;   a first sensor configured to respond to a first and a second material in an environment, wherein the first sensor is one of a metal oxide sensor, an electrochemical sensor, a photoionisation sensor, an infrared sensor, a pellistor sensor, an optical particle monitor, a quartz crystal microbalance sensor, a surface acoustic wave sensor, a cavity ring-down spectroscopy sensor or a biosensor;   a second sensor configured to respond to a first and a second material in an environment, wherein the second sensor is another of a metal oxide sensor, an electrochemical sensor, a photoionisation sensor, an infrared sensor a pellistor sensor, an optical particle monitor, a quartz crystal microbalance sensor, a surface acoustic wave sensor, a cavity ring-down spectroscopy sensor, a biosensor or a field effect transistor sensor;   wherein the processor is configured to:
 measure a response of the first sensor to the first or second material; 
 measure a response of the second sensor to the first or second material; and 
 determine from first and second sensor measurements, a presence, concentration or change in concentration of the first and/or second material. 
   
     
     
         11 . The system according to  claim 10 , further comprising a source of the first material; and
 wherein in response to the first or second material being above or below a threshold the processor is further configured to release the first material into the environment.