What is one key safety precaution when using electrical equipment in a barbershop?

Ensuring all devices are properly grounded to prevent shock is a critical safety precaution when using electrical equipment in a barbershop. Grounding helps to direct any stray electrical current safely into the ground rather than through a person, significantly reducing the risk of electric shock. This is particularly important in a barbershop environment where water and damp conditions can increase the likelihood of electrical hazards. Proper grounding can provide a necessary line of safety, ensuring that equipment like clippers and hairdryers are safe to use and won't pose a risk to both clients and barbers.

The other choices do not provide adequate safety measures. Relying solely on extension cords can lead to tripping hazards and potential overloading of circuits. Keeping devices only in dry areas is not sufficient because wet conditions can occur unexpectedly. Using devices with outdated wiring poses a significant risk, as old wiring can be frayed or damaged, increasing the likelihood of electrical failures or fires.