SCBA cylinders are made of which materials?

• A. Plastic and rubber
• B. Steel and Aluminum
• C. Glass and Ceramic
• D. Composite fibers

Answer: (B)

SCBA cylinders are high‑pressure vessels, so the material must provide reliable strength, durability, and cost‑effectiveness for repeated filling and use. Steel and aluminum have a long, proven track record in firefighting gear, offering the right balance of toughness, weight (aluminum is lighter than steel), and ease of manufacture and testing. While newer composite cylinders (carbon fiber or fiberglass wrapped around a liner) exist and can be lighter, they introduce different maintenance and inspection considerations and are not the standard material described in many basic training contexts. Plastic, rubber, glass, and ceramic don’t deliver the required combination of strength, toughness, and weight for the cylinder walls in typical SCBA use, so steel and aluminum are the correct materials to emphasize.