Which statement describes a stand-alone dental unit?

• A. They are integrated into the chair system.
• B. They have their own pedal separate from the dental unit rheostat.
• C. They require a separate power supply for each tool.
• D. They are battery-powered and portable.

Answer: (B)

Stand-alone dental units are modular systems that operate independently of the dental chair. A key feature is that they have their own foot pedal for operating the handpieces, separate from the chair’s own control (the rheostat), which typically manages chair movement rather than instrument speed. This separation lets you control the handpieces and other tools directly from the unit without affecting how the chair moves, and it supports flexibility in room setup or chair interchange.

The other ideas don’t fit as well: being built into the chair would mean it isn’t stand-alone; most stand-alone units aren’t battery-powered or portable in the sense implied, and you don’t usually need a separate power supply for each tool—the unit generally shares a single power source for all tools.