I am trying to figure out the right way to measure H2S with the MQ-136 sensor

Hi i am new here, And i am currently working on a project for a biogas monitoring system. I am currently working on the sensor as i am speaking. And i would like to ask about how do i make sure that the sensor i am using is calibrated properly for its intended use. And for more information this is a sensor that i bought online with the module included. This is the source code i am working on:

#define MQ136_PIN 34
#define VCC 5.0 

float Ro = 17000; 

void setup() {
    Serial.begin(115200);  
    Serial.println("MQ-136 H2S Sensor Initialization...");
}

void loop() {
    int sensorValue = analogRead(MQ136_PIN);
    float Vout = sensorValue * (VCC / 4095.0);  // Convert ADC value to voltage

    float Rs = (VCC - Vout) * Ro / Vout;

    float ratio = Rs / Ro;

    float H2S_ppm = 10 * pow(ratio, -1.43);  

    // Print results
    Serial.print("Raw ADC Value: ");
    Serial.print(sensorValue);
    Serial.print(" | Voltage: ");
    Serial.print(Vout, 2);
    Serial.print("V | Rs: ");
    Serial.print(Rs);
    Serial.print(" ohms | H2S Concentration: ");
    Serial.print(H2S_ppm, 2);
    Serial.println(" ppm");

    delay(1000); 
}

I am just aking opinions on should i go to company that has a calibration service to help me on making sure that the sensors are producing the right outputs or should i just stick to the datasheet and experiment more?

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