When is a ground fault circuit interrupter (GFCI) required?

A ground fault circuit interrupter (GFCI) is specifically required in areas where water is present due to the increased risk of electrical shock. This includes locations like kitchens, bathrooms, laundry rooms, and outdoor spaces. The presence of water increases the chances of electrical current taking an unintended path, which can lead to severe injuries or fatalities.

The National Electrical Code (NEC) has clear guidelines for GFCI installation in these wet or damp areas to enhance safety. By having GFCIs in locations where exposure to moisture is common, the risk of ground faults is mitigated, providing an important layer of protection to both individuals and property.

In other settings, such as industrial environments or general residential installations, while GFCIs may be beneficial and sometimes required, the specific stipulation about water presence makes the correct answer focused on these high-risk areas. Outdoor electrical systems may also need GFCIs, but they are not the sole requirement compared to those interiors with water presence. Thus, the focus of GFCI usage is most critical in the context of water exposure, which is why the answer emphasizes this necessity.