To hide the technician account at setup of new device or in the creation of an image type the following in terminal :
sudo dscl . create /Users/hisechnician isHidden 1
press return and you will be asked to enter a password which belongs to the histechnician account .. next type :
sudo mv /Users/histechinician /var/histechnician
press enter .. no password is asked for here but if there is its the histechnician account p/w .. next type :
sudo dscl . create /Users/histechnician /var/histechnician NFSHomeDirectory
hit enter .. no password here but if there is its the histechnician account p/w
These 3 commands will hide histechnician account from the systems preferences, users folder and also from the login interface.