Which statement about NFPA 99 color coding for pipe labeling is correct?

• A. Color coding is required
• B. Color coding is optional
• C. Color coding is prohibited
• D. Color coding depends on gas type

Answer: (A)

NFPA 99 requires that medical gas piping be color coded to identify the gas carried, so clinicians and staff can quickly and accurately distinguish between different systems and prevent dangerous misconnections. This is a mandatory requirement, applying across medical gas lines and related outlets, not something optional or only for certain gases. The standard outlines a specific color scheme and labeling that facilities must follow, with local codes often adopting or reinforcing those practices. While additional labeling may exist in some settings, the core point is that color coding is required to ensure safe and reliable gas delivery.