Class 8
Class 8 — corrosives
Class 8 is corrosive materials, including common acid and caustic tank-car loads.
Class 8 is corrosives. Acids and caustics both land here. The placard does not tell you which direction the material attacks — acid versus base — and that difference matters. The identification number does.
Sulfuric acid, hydrochloric acid, and sodium hydroxide solution are three class 8 loads you can tell apart by number: 1830, 1789, and 1824. Calling all three "acid" is wrong, and it throws away the thing the placard went to the trouble of saying.
Corrosive loads are a reason the tank specification and the placard are a pair. The placard is the contents today. The specification stencil is the tank. Neither one replaces the other.
Identification only. If a car is leaking or in a wreck, move away and call your local emergency number. Responders use the Emergency Response Guidebook. This page is not that book.