Lifebar Help

Hi, I have created a lifebar which decreases in increments when a Healthfield is entered and a trigger is activated by the Player. It works well but I cannot understand how to load a new scene when 3 negative increments have been reached. Can anyone help on this? Here is my current code for the Healthfield…

var Hurtbox: boolean = false;

function OnTriggerEnter(other: Collider){
if(other.gameObject.tag == ("Player")){
if(Hurtbox && LifeBar.Health >= 0){
LifeBar.Health--;
}
else if(!Hurtbox && LifeBar.Health<=2){
LifeBar.Health++;
}
//Destroy(gameObject);
	}
}

Try these 2 videos:

http://www.unity3dstudent.com/2010/09/beginner-b20-if-statements-and-booleans/

http://www.unity3dstudent.com/2010/07/beginner-b16-switching-scenes/