Handle Corrosive Acids and Caustics Safely

Understand the corrosivity hazards of acids and caustics, and follow these guidelines to manage those hazards through inherently safer design, engineering and administrative controls, and personal protective equipment.

Two common characteristics of acids and caustics are that they tend to be corrosive, and they are encountered throughout the chemical process industries (CPI). They can damage human tissue, and attack many of the materials of construction in CPI plants (including steel and concrete). Many acids react with metals to produce hydrogen gas, creating a flammability hazard. Most corrosive liquids and gases are strongly reactive — as oxidizers (e.g., nitric acid) or reducing agents (e.g., sulfur dioxide) — and are incompatible with many other common chemicals. Acids and caustics may release corrosive vapors at room temperature when in a concentrated form (e.g., nitric acid, hydrochloric acid) or in the form of dust (e.g., sodium hydroxide). Many acids and some caustics are toxic. In addition, some chemicals become acidic when they come into contact with water or humid air (e.g., acetic anhydride, sulfur trioxide).