You have been assigned to be the classroom waste management monitor. One part of your job is to keep track of what is thrown away in the classroom.

Below are items that you found in the trashcan. You must decide if the item should have been reused, recycled, or thrown away.

Drag each item to the appropriate disposal choice for that item. If your answer is correct, the item will remain in the box.

Another part of your job is to help clean up after experiments: One day you find several items have been left out in the lab by forgetful students. You must determine the proper handling of these items.

First, refer to the Disposal Methods Index and identify the item.
(Source: Laboratory Safety Guide Appendix A, University of Wisconsin - Facilities, Planning & Management)

Next, refer to the Disposal Method Descriptions to determine proper disposal practices for the item.
(Source: Laboratory Safety Guide Chapter 7, University of Wisconsin - Facilities, Planning & Management)

In your notes, record the correct disposal technique. Did you make the right decisions?
Compare your answers with those in table below by clicking on Check Your Answer:

Material	Disposal Method
Lye	Interactive popup. Assistance may be required. Check Your Answer Neutralize Base 1: General base neutralization such as solutions of potassium and sodium hydroxides and alcoholic sodium or potassium hydroxide cleaning solutions Slowly add 6 N hydrochloric or other suitable acid, but not concentrated sulfuric acid. Monitor pH changes with pH paper or phenolphthalein. Note: Universal indicators can air oxidize rapidly in basic solutions giving a false color change. When pH < 10 is reached, the solution can be washed down sanitary sewer with a water rinse to clear the trap.
Hydrochloric acid 37% aqueous solution	Interactive popup. Assistance may be required. Check Your Answer Neutralize Acid 2: Concentrated acids such as formic, hydrochloric, acetic, and phosphoric acid Pour amount of acid specified above slowly into water. Stir in 6 M sodium or potassium hydroxide solution (or other suitable base) while monitoring the pH change with Universal indicator or check periodically with pH paper. Once a pH of > 2 is reached, the solution can be washed down the sanitary sewer using a large amount of tap water to clear the traps. For acetic and phosphoric acids, the pH change is more gradual with a base addition.
Zirconium Oxide	Interactive popup. Assistance may be required. Check Your Answer Normal Trash 1: Nonhazardous solid chemicals Use this procedure for nonhazardous solid chemicals that are listed as Normal Trash 1 in Appendix A, such as talc, silica, sulfur and carbon. Do not dispose of liquids or solutions in the normal trash. Normal trash is handled roughly. To prevent exposing handlers to powders, all waste solids should be contained in a tightly closed bag, box or bottle that is packed inside a second box or bag (i.e., an over-pack). A box over-pack is preferred, especially to prevent breakage if glass is used as an inside container. Mark the over-pack with the waste's identity so that handlers can be assured that the waste is safe for the normal trash. To further minimize the chance of breakage from handling, place more than one kilogram of a nonhazardous chemical for the normal trash directly in your building's dumpster. Be careful about putting containers that have a "chemical" label or those if put in a lab waste basket may be viewed as misplaced by the custodians and brought to someone's attention. Persons who are unaware of the potential hazards of chemicals are often over cautious.
3 AAA batteries	Interactive popup. Assistance may be required. Check Your Answer There are four types of batteries used on campus: automotive, ordinary alkaline, those containing a toxic metal (e.g., cadmium and mercury), and flammable. Each of these battery types requires a different disposal procedure. Ordinary alkaline batteries (e.g., zinc-manganese dioxide) can be disposed in the normal trash.
Sodium Iodide	Interactive popup. Assistance may be required. Check Your Answer Sanitary Sewer 1: Readily soluble solids, solutions and nonvolatile liquids Soluble organic salts, sugars, amino acids, nucleotides, nucleosides, vitamins, acids, amines, surfactants, and the many metabolic intermediates can all be disposed of in the sanitary sewer. In addition, soluble salt combinations of these ions can be discharged to the sanitary sewer system: Follow Guidelines For Sanitary Sewer Disposal, above. For each chemical or solute, limit discharges to 1000 grams per day per principal investigator. Look at the label to see if it is an anhydrous aluminum, magnesium chloride, or bromide (see Sanitary Sewer 3). Slowly pour the substance into a stream of running water down the drain.