diff --git a/examples/MQ-4-LINEAR/MQ-4-LINEAR.ino b/examples/MQ-4-LINEAR/MQ-4-LINEAR.ino
index f41557e..aee7669 100644
--- a/examples/MQ-4-LINEAR/MQ-4-LINEAR.ino
+++ b/examples/MQ-4-LINEAR/MQ-4-LINEAR.ino
@@ -85,7 +85,10 @@ void loop() {
   //https://jayconsystems.com/blog/understanding-a-gas-sensor 
   MQ4.setA(-0.318); MQ4.setB(1.133); // A -> Slope, B -> Intersect with X - Axis
   float LPG = MQ4.readSensor(); // Sensor will read PPM concentration using the model and a and b values setted before or in the setup
-  
+
+  //  exposure to 2000 ppm of LPG gas is immediately dangerous to life and health. In this section
+  if(LPG>=2000) Serial.println("Warning - Very high concentrations detected!");
+
   Serial.print("|                "); Serial.print(LPG);
   Serial.println("                |");