   dtostrf(bar, 3, 2, _g);
   dtostrf(lux, 1, 0, _l);
   dtostrf(no2, 1, 0, _n);
-  dtostrf(sound, 1, 0, _s);
+  dtostrf(sound, 1, 1, _s);
   dtostrf(tvoc, 1, 0, _v);
   delay(50);
   

// define TSL2561 global variables
long lux;
float bar;
int sound;
float co;
float no2;


  

  // ADMP401 mic for sound level
  float sumADC=0.0;
  for(int i=0;i<5;i++)
  {
     sumADC = sumADC + analogRead(A0); // take avg of 5 readings
  }
  float averageADC = sumADC/5.0;
  float volts = (averageADC/1023.0 * 3.3);
  sound = (20 * log10(volts/0.007943)) - 42 + 94 - 60;  // VRMS = 0.007943; -42dB is sensitivity of ADMP401 mic; 1 Pa = 94 dB SPL RMS; 60dB is gain of amplifier
  // the above is uncalibrated sound level - needs to be calibrated with reference to an accurate sound level meter in varying SPLs, frequencies and environments.
    


  // MPL3115A2 air pressure sensor
