Allow content builder to 'disable' a content type form
I think you'll have to do this with code.  My quick take on this would be:


Create a content type with an "Disallow jobs" check box and the body field.  
Allow the technician role to view and edit this content type.
Create a node and add it to your menu with a "Disable/Enable jobs" link.


Use hook_form_alter() to:


check for the job content type form
load your Disable / Enable jobs node
Check if the disable jobs checkbox is ticked.
Replace the $form array with a markup entry using the text from the node.


Note if you need to have this turned off automatically (e.g. lab closed), you probably can use rules to modify the disable jobs node.