if (document.images) {
	imgWater_on =new Image();  imgWater_on.src ="/global/assets/images/en/subNav_operating_engineering_water_ON.gif"; 
	imgWater_off=new Image();  imgWater_off.src="/global/assets/images/en/subNav_operating_engineering_water_OFF.gif"; 
	
	imgAir_on =new Image();  imgAir_on.src ="/global/assets/images/en/subNav_operating_engineering_air_ON.gif"; 
	imgAir_off=new Image();  imgAir_off.src="/global/assets/images/en/subNav_operating_engineering_air_OFF.gif"; 
	
	imgInsulation_on =new Image();  imgInsulation_on.src ="/global/assets/images/en/subNav_operating_engineering_insulation_ON.gif"; 
	imgInsulation_off=new Image();  imgInsulation_off.src="/global/assets/images/en/subNav_operating_engineering_insulation_OFF.gif"; 
	
}