Final answer:
To improve safety on an ungrounded circuit, a ground fault circuit interrupter (GFCI) should be installed. This device prevents electric shock by quickly detecting current imbalances and interrupting the circuit flow.
Step-by-step explanation:
Installing a ground fault circuit interrupter (GFCI) on an ungrounded circuit with ground type receptacles will improve the safety of the system. The role of the GFCI is to prevent shock by detecting the loss of current to unintentional paths, such as through a person's body or water on the floor. It is especially crucial in areas likely to be wet, where a faulty appliance lacking a proper earth/ground connection can pose a severe risk of electric shock. If the GFCI detects an imbalance in the circuit, it will quickly trip, thereby cutting off the electricity and mitigating the risk of injury or damage. This device is a standard safety measure in bathrooms and kitchens where the risk of electric shock is higher due to the presence of water.