CalDigit RAID Card - Manual (Page 8)

8 A. MacPro
1.2 Turn Off / Shut Down your computer
Turn off your computer. Touch the metal on the outside of your Mac Pro
(chassis) while it’s still plugged in to discharge any static electricity from
your body.
1.3 Open your computer case
Remove the side panel. Let the computer cool down. Its internal
components can still be very hot even when the computer is off.