Q. Are there any other methods of waterproofing before tile is installed?
A. Yes. There is another product which consists of a neoprene membrane. This membrane is about 3/16 in. thick and can be molded to the pan and glued in the corners with a special glue. Some tile contractors use this product on remodeling projects where they are the sole contractor--in other words no one else will be walking all over the pan potentially causing damage. Note that they make ABS drains specifically for neoprene. You can use either type of drain for neoprene, but you can only use a cast iron drain for hot mopping--see below.
LEFT: This is the correct drain for a hot tar shower pan. It comes with two halves that are bolted together. It is made of cast iron not ABS plastic! The bottom half is fitted onto the drain pipe. Notice the top of the bottom half of the cast iron drain is flush with the subfloor and that the bottom half of the drain is embedded in the concrete--this is what it should look like!
RIGHT: Neoprene drains are of ABS plastic and are not suitable for hotmopping! Don't be confused, I've had alot of customers install a drain from Home Depot that is similar to this one. They get confused by the fact that it has a label that reads "SHOWERPAN DRAIN" in bold letters--Don't buy it unless you plan on using neoprene! Look around, you should see the cast iron drains (as shown in the left picture) nearby.