Capt_ron. A clean room is an absolute MUST have when dismantling hard drives. A great example that will show you why is to take a piece of black paper hold it up to your head; and run your hand through your hair. Then, rub your hands together over the same piece of paper. Notice the skin flakes that appear .Those little particles can do huge damage to a hard drive.
So, it is not only necessary, it is imperative to have a clean room. However, the definition of clean room is really "a spot where you can achieve less than .03 microns of junk in a parts per million mixture." So, a "clean bench" with lint free, dust free clothing will do the job. There are a number of companies who make "clean benches." I imported mine from China. The price was great compared to anything in the US. Hope it helps. If you have questions, you can ask at http://techrxgb.com