If you have Public Profile turned off (which is the default), then No. Your availability will only visible to employers that have invited you to connect within the app and only once you have then accepted their invite. 

A list of these employers (Joined) can be viewed in your Profile screen within the app.

If you turn on Public Profile (in the Profile screen), this will enable other Employers using the canuwork app within your area to view your Availability and potentially send you a work request.

Once Public Profile is on, within the Profile screen you will see a Nearby menu item and assuming you have your location set (suburb/city), then tapping Nearby will display any Employers using canuwork within the distance range (defaults to 50kms).

You can also switch off any Employers which you may not want to work for which will mean they can no longer view your Availabiliy, even with Public Profile turned on.