ANSWER 2  
As a basic guideline, you are requested to use your right hand for hand verification. It is designed for right hand as you can see the arrangement of the pins coming out of the silver plate ( called ¡®platen¡¯ ) where you place your hand. It is ,however, possible to use left hand when you hurt your right hand badly. The way how you use left hand is to place you hand upside down ( see picture ). Since the reader is reading your hand in 3D image, it will not care the side of the hand as long as all finger touch all pins. In the extreme ( and unfortunate ) cases, there are staffs who do not have 4 fingers in one hand due to the past accident or something to that nature. For those special staffs, there is a function called ¡° special enrollment¡± which you can identify the person only with their PIN number. This special feature is to be utilized as a last resort since it will affect the integrity of the biometrics system directly.