Category:Articles with unknown NFPA 704 code

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Unknown NFPA 704 codes used. Articles are sorted by F, H, R, or S depending on the unknown code.

When there are multiple unknown codes, the article will be sorted under any one letter. So a page with an erroneous "F=7" code may be under "R" when that has an error too (like "R=5"). All error articles are in this category -- somewhere. Populated by {{NFPA 704 diamond}} (see its documentation). Note that code "S" (Special) is used, not "O" (Other).