Which indicators may appear in the white section of the NFPA 704 diamond?

Which indicators may appear in the white section of the NFPA 704 diamond?

• A. Numerical scale for health
• B. Color coding for packaging
• C. W or OX
• D. Temperature range

Answer: (C)

In the NFPA 704 diamond, the white section is for special hazards. You’ll often see markings like W or OX in this area. W means water reactivity—the material may react with water, so water should not be used for suppression or contact unless specifically advised. OX stands for oxidizer, a substance that can intensify fires and requires special handling and separation from fuels. These white-section indicators provide guidance beyond the colored hazard ranks (health, flammability, reactivity) and are essential for safe response. That’s why the indicators that may appear in the white section are W or OX.

In the NFPA 704 diamond, the white section is for special hazards. You’ll often see markings like W or OX in this area. W means water reactivity—the material may react with water, so water should not be used for suppression or contact unless specifically advised. OX stands for oxidizer, a substance that can intensify fires and requires special handling and separation from fuels. These white-section indicators provide guidance beyond the colored hazard ranks (health, flammability, reactivity) and are essential for safe response. That’s why the indicators that may appear in the white section are W or OX.