// Detect if browser is Netscape 3 + or IE 4 +.
bName = navigator.appName;
bVer = parseInt(navigator.appVersion);
    if ((bName == "Netscape" && bVer >= 3) || 
        (bName == "Microsoft Internet Explorer" && bVer >= 4)) br = "n3"; 
    else br = "n2";

    if (br== "n3") { 
    img1on = new Image();                    
    img1on.src = "images/home_on.jpg";        
    
    img1off = new Image();              
    img1off.src = "images/home_off.jpg"; 

    img2on = new Image();                    
    img2on.src = "images/Why_on.jpg"; 

    img2off = new Image();              
    img2off.src = "images/Why_off.jpg"; 

    img3on = new Image();                    
    img3on.src = "images/Design_on.jpg"; 

    img3off = new Image();              
    img3off.src = "images/Design_off.jpg";

    img4on = new Image();                    
    img4on.src = "images/Mechanical_on.jpg"; 

    img4off = new Image();              
    img4off.src = "images/Mechanical_off.jpg"; 

    img5on = new Image();                    
    img5on.src = "images/Duct_on.jpg"; 

    img5off = new Image();              
    img5off.src = "images/Duct_off.jpg";
    
    img6on = new Image();                    
    img6on.src = "images/Training_on.jpg"; 

    img6off = new Image();              
    img6off.src = "images/Training_off.jpg"; 
    
    img7on = new Image();                    
    img7on.src = "images/Service_on.jpg"; 

    img7off = new Image();              
    img7off.src = "images/Service_off.jpg";
        
    img8on = new Image();                    
    img8on.src = "images/Contact_on.jpg"; 

    img8off = new Image();              
    img8off.src = "images/Contact_off.jpg";               
    }

function imgAct(imgName) {
    if (br == "n3") {
    document[imgName].src = eval(imgName + "on.src");
    }
}

function imgInact(imgName) {
    if (br == "n3") {
    document[imgName].src = eval(imgName + "off.src");
    }
}