Death scene/screen on player Health Script Wont work!

using UnityEngine; using System.Collections;

public class global:MonoBehaviour {

 public int currentHealth;
 public int maximumHealth = 100;

 public float hbLength;

 // Use this for initialization
 void Start () {
     currentHealth = maximumHealth;

     hbLength = Screen.width / 2;
 }
 
 // Update is called once per frame
 void Update () {
     ChangeHealth(0);
 }
 
 void OnGUI () {
     GUI.Box (new Rect(10, 10, hbLength, 25), currentHealth + " / " + maximumHealth);
 }

 public void ChangeHealth (int health) {
     currentHealth += health;
     hbLength = (Screen.width / 2) * (currentHealth / (float)maximumHealth);

     if(currentHealth <= 0)
     {
         Application.LoadLevel(9);
 
     }
 }

} I made this Player Health script with the hope to just add a death scene when my health hits 0 but it wont work the health portion works great it is just that it wont load my level, i am new to unity so any help is very appreciated, thanks.