What type of structure requires ground fault circuit interrupter (GFCI) protection?

Ground fault circuit interrupter (GFCI) protection is specifically required in areas where there's an increased risk of electric shock due to moisture. Bathrooms are a primary area where GFCI protection is mandated. This is because they often contain water sources, such as sinks and tubs, which can increase the likelihood of electrical current flowing through water, posing a safety hazard.

In bathrooms, GFCI outlets help prevent potentially lethal electrical shocks by quickly interrupting the flow of electricity if they detect any imbalance between the incoming and outgoing current. This rapid response can make all the difference in a potentially dangerous situation.

While garages may also require GFCI protection due to the potential for water exposure from vehicles, bathrooms are universally recognized as high-risk areas warranting this safety feature. Other spaces like living rooms and bedrooms typically don't present the same imminent risk of moisture, which is why GFCI protection is not generally required in those locations.