Below are instructions for updating the firmware on a Mac. It is recommended to have the most up to date firmware on your Mac prior to running WipeDrive.
To perform a simple firmware update:
1. Navigate to About This Mac
2. Click Software Update...
3. Click Install
To perform a manual firmware update:
1. Browse Apple support pages to find the desired EFI firmware update for your specific Mac
2. Download the relevant .dmg file containing the update
3. Double click .dmg file to open its contents. You should now see a .pkg file
4. Double click the .pkg file to launch the firmware installer
5. Follow the on-screen instructions to complete the update.
Screenshots from www.chriswrites.com