What does the yellow diamond symbol signify according to NFPA?

The yellow diamond symbol in the National Fire Protection Association (NFPA) labeling system signifies a potential combustion hazard. This symbol aims to alert individuals to the risk associated with the materials contained within a storage unit or cylinder. Specifically, the yellow color, along with its position and design, communicates that the substance may ignite under certain conditions, thereby posing a fire risk.

Understanding the significance of this symbol is crucial for safety in environments where non-flammable medical gases are handled. Recognizing that a yellow diamond indicates the potential for combustion helps ensure that appropriate precautions are taken during the storage and use of such materials, which is vital in preventing accidents and maintaining a safe working environment.

The other choices do not accurately reflect the meaning of the yellow diamond symbol. For example, the symbol does not indicate that a container is safe to use, nor does it designate a specific type of gas or its recycling status.