Speaker 1: Welcome to Brainstuff from house stuff works dot com where
Speaker 1: smart happens. Hi. I'm Marshall Brain with today's question. What
Speaker 1: do those big diamond shaped signs with red, yellow, and
Speaker 1: blue squares on the mean when you see them on
Speaker 1: the sides of buildings. You see these signs on any
Speaker 1: building that contains hazardous chemicals. The sign is called an
Speaker 1: nfp A panel. N f p A stands for the
Speaker 1: National Fire Protection Association. The idea behind these signs is
Speaker 1: to give firefighters some sort of advanced notice on what
Speaker 1: they're getting themselves into when they arrive at the scene
Speaker 1: of a fire. When there's a house fire, firefighters have
Speaker 1: a pretty good idea of what they're in for, but
Speaker 1: if there's a fire at a warehouse in an industrial park,
Speaker 1: it is very hard to know what chemicals might be
Speaker 1: stored there. The n f p A panel is a
Speaker 1: clear indication of what sort of dangers might lie inside.
Speaker 1: The panel has four different areas. The red area is
Speaker 1: the fire hazard area, the blue is the health hazard area,
Speaker 1: the yellow is the reactivity area, and the white is
Speaker 1: a specific hazard area. The numbers in the first three
Speaker 1: areas range from zero to four, with zero signifying no hazard,
Speaker 1: and four signifying a severe hazard. For example, in the
Speaker 1: reactivity area, zero means stable, one means unstable if heated,
Speaker 1: two means a violent chemical, three means shock or heat
Speaker 1: may detonate, and four means may detonate on its own.
Speaker 1: In the fire hazard area, the numbers indicate the flash point.
Speaker 1: Zero means it won't burn, one means it will burn
Speaker 1: above two hundred degrees, two means it will burn below
Speaker 1: two hundred degrees, three means it will burn below one degrees,
Speaker 1: and four means it will burn below seventy four degrees fahrenheit.
Speaker 1: Concrete is an example of a class zero fire hazard.
Speaker 1: It won't burn paper and wood, or class one. In
Speaker 1: the health hazard area, zero means no hazard, one means
Speaker 1: slightly hazard as, two means hazardous, three means extremely hazardous,
Speaker 1: and four means deadly. In the specific hazard area, which
Speaker 1: is the white square at the bottom of the diamond,
Speaker 1: you'll see things like O X Y or oxy for oxidizer,
Speaker 1: acid for acids, a O K for alkali, cr for corrosive.
Speaker 1: You may also see a W with a bar through
Speaker 1: it meaning use no water, or a radiation hazard symbol
Speaker 1: for radioactive materials now you can drive around your neighborhood
Speaker 1: and get a glimpse into what is stored in all
Speaker 1: those buildings. Do you have any ideas or suggestions for
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