Set checkbox status On Load

Set checkbox status On Load

Hi Folks,
 
I have a Form with a checkbox for nine survival equipment options. I have been asked that when the Form loads, that some of these options are checked on by default. Seems a simple request, eh!
 
So far, I have been unable to add a statement to the On Load script that can achieve this. I can usually find the answers to my problems searching the forum but no luck in this case.
 
Can someone set me on the right track please? Many thanks.