What color is breathing oxygen cylinder?

• A. Blue with a red band
• B. Yellow with a black band
• C. Red with a white band
• D. Green with a 3 inch wide white band around the upper circumference of the cylinder

Answer: (D)

Identifying breathing oxygen cylinders is about color coding and markings that let you recognize the contents at a glance for safety and proper handling. The best indicator is a green cylinder body with a wide white band around the upper circumference. The green base color signals oxygen, and the broad white band clearly marks it as breathable oxygen, making it easy to spot in a cockpit or maintenance area. The band’s size and position—about 3 inches wide around the upper part—enhance visibility from a distance and under low-light conditions, which helps prevent misidentification during preflight checks or emergencies. The other color schemes described do not match this standard and could lead to confusion about what’s inside, so they’re not the correct identifiers for breathing oxygen cylinders.