The Red Quadrant: Decoding the NFPA Red Diamond Meaning for Every Substance
The NFPA red diamond meaning is simple at first glance: it points to flammability risk. The problem is that job sites, labs, manufacturing areas, contractors, and temporary storage zones often treat that red number like a quick label instead of a planning signal. A red 1, red 2, red 3, or red 4 can change…