A brown cylinder is designated for which type of materials?

• A. Non-toxic household items
• B. Toxic and poisonous materials
• C. Flammable liquids
• D. Compressed gases

Answer: (B)

Color coding on compressed gas cylinders is a quick way to signal what’s inside and the associated hazard. A brown cylinder is designated for toxic and poisonous materials, so this color tells you to treat the contents as hazardous and to take appropriate precautions—use in a well-ventilated area, avoid inhalation, wear proper protective equipment, and follow all labeling and safety data sheets.

Other options don’t fit this color convention as the brown color is specifically tied to toxic/poisonous materials. Flammable liquids are typically marked or colored to indicate flammability (often red or with “flammable” wording), and non-toxic household items wouldn’t be stored or labeled in the same compressed-gas cylinder color system. Compressed gases is a broad category, but the brown color is not used to denote all compressed gases—it denotes toxic ones.