Acids stronger that pH 2.0 and bases stronger than pH 12.0 are not to be poured directly down the drain even if done so with copious amounts of water. These materials should be sufficiently diluted and/or neutralized in a safe and effective manner to the desired pH limit. The resulting weak acid (> pH2) or weak base (< pH12) can then be poured down the drain along with a moderate flow of tap water. The SEAS stockroom has pH paper available for testing of these pH levels before disposal.
If for any reason this neutralization is difficult or unadvisable, strong acids or strong bases can be collected in carboys for disposal as hazardous wastes. The EQuad stockroom maintains a supply of free carboys, and EHS can replenish or supplement this supply on request. Please use the blue carboys for acidic or basic waste. Alternatively, collect the waste in its original container if that is more practical in terms of space.