Corrosive

Corrosive and caustic chemicals destroy metal, plastic, and human tissue.

Chemicals are considered hazardous when their pH < 2.0 (corrosive) or pH > 12.5 (caustic). Chemicals are also considered hazardous if they corrode steel at a rate greater than 0.250 inch per year.

Examples include:

1. phosphoric acid
2. potassium hydroxide

Note: Some acids and bases may be neutralized to a pH between 5.5 and 12.0 and discharged to the sewer instead of being handled as hazardous waste. The sewer limits are more stringent than the hazardous waste rules because they are designed to protect concrete sewer pipes.