🔍 Key Concepts

• Self-Contained Breathing Apparatus (SCBA) air flow path (cylinder → high‑pressure regulator → low‑pressure regulator → facepiece) • Normal operation of the regulator versus emergency bypass operation • The purpose of a bypass valve in emergency use only

💭 Think About

• In an emergency, what problem is the bypass valve designed to solve: lack of air to the user, too much air, or something else? • Think about what part of the system the air must go around (or skip) so the wearer can still breathe if that part fails. • Which component actually controls the pressure and flow of air to your mask during normal operation?

✅ Before You Answer

• Identify which component normally reduces and controls pressure to breathing level. • Confirm which choice describes something that realistically exists on standard SCBA (e.g., is there a regenerator on typical firefighting/emergency SCBA?). • Ask: in an emergency, do we want to vent oxygen to the atmosphere, or ensure oxygen/air still reaches the facepiece?