Disposal of waste

The following are examples of materials which must never be put down the sink:

	Mercury and its compounds (Return to the mercury residue bottle.)
	Liquid nitrogen (Allow it to evaporate.)
	Non-aqueous solvents (The laboratory is equipped with waste solvent containers. Do not mix halogenated and non-halogenated solvents. Some of these mixtures are dangerous and could involve the department in considerable expense in disposing of them.).

Dilute aqueous solutions and suspensions of solids may be disposed of down the sink if they are relatively non-toxic. They must be washed down with copious quantities of water. Harmless solids should be returned to the service room in bottles labelled appropriately.

When you need to dispose of material not covered by the above, seek advice from the technical staff: such material may need to be stored in a separate container. After rinsing out glassware that has been in contact with particularly toxic material, which will be indicated in the experimental handout where appropriate, return it to the service hatch and inform the technical staff accordingly.