I called the customer to let them know I would be by to do the semi-annual inspection and service of the kitchen Range Guard System. Upon arrival I inspected it to look for any damage or possible items that might need to be replaced. I then put it in test mode. Once in test mode I tested it to make sure it would function as it is supposed to. Once this was done and the system was functioning well, I replaced the fusible links and foil seals. I then put the system back to operational mode. I wrote the report and let the customer know that they needed to get it done every 6 months.