This process takes about 10 to 20 minutes dependent on staffing.  If somebody gets to you right away, it can go fairly fast.  After you lay down on the lounge chair, you are asked to identify yourself by reciting your name and social security number and address, just in case somebody has kidnapped you, thrown you in a corner and gone in your place.  Sort of like Airport Security but even more lame.  I don't ask why, I just recite and close my eyes and then I imagine a sandy beach in Hawaii through an alcoholic haze.

An empty pint bag is placed on a scale and the nurse pokes a vein in the crotch of your arm and the blood starts to flow.   A pressure cuff placed on your upper arm, is used to ensure your blood does not flow to

quickly.  You squeeze your hand to help the blood flow and eventually, the weighing machine buzzes indicating the bag is full.  This usually takes between five and ten minutes.

The nurse clamps the flow to the bag and then she then fills about 6 small test tubes with blood for lab testing. 

Curious thing about the test tubes.  They have a small vacuum and the blood is actually sucked into the tubes, expediting this whole process.  After that, she removes the needle in the crotch of your arm, swabs and cleans the area again and then wraps a piece of gauze around the wound to insure it stays clean and heals.  You are then asked to walk to the lounge area.