At Walmart the other day I spotted this fire diamond. It was randomly there on a wall on the side of the store, with seemingly no explanation. There were no chemical tanks or anything near the sign, but there was a door that was a little bit away.

I cannot find anything that has this fire diamond, let alone a corrosive oxidizer.

Any help in finding this mystery chemical is appreciated.

The fire diamond is shown below. It does use the informal "COR" symbol, which means corrosive.

enter image description here

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    $\begingroup$ There's probably many examples that would fit. $\endgroup$
    – Mithoron
    Apr 5 at 18:16
  • $\begingroup$ I can't find one. $\endgroup$ Apr 5 at 18:17
  • $\begingroup$ Well, that's a matter of right method of searching, probably best to go through the original source like andselisk did: chemistry.stackexchange.com/questions/85342/… $\endgroup$
    – Mithoron
    Apr 5 at 18:24
  • $\begingroup$ I've tried finding a place that can search for chemicals by fire diamond. I can't seem to find one. $\endgroup$ Apr 5 at 18:42
  • $\begingroup$ The final values in the diamond are a combination of all chemicals within the placarded area. Whether that is from one single chemical, or multiple, is not definable from just the placard. $\endgroup$
    – Jon Custer
    Apr 5 at 19:31

1 Answer 1


I agree with Jon Custer's comment. This symbol (see below) is not for any specific chemical:

3-4-2-COR_OXY Hazard Level Indicator

The ComplianceSins.com says following about this NFPA 704 Diamond with 3-4-2-COR_OXY Hazard Level Indicators:

Please NOTE: The symbol in the white Special Hazard area of this specific diamond is not considered an "authorized symbol" by the NFPA. Before using this symbol, consult your local emergency response team regarding the use, size and placement of non-authorized NFPA symbols with your NFPA diamond.


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