D waste disposal as you work in the laboratory

D. Waste Disposal
As you work in the laboratory, chemical wastes are produced. Although we will use small quantities of materials, some
waste products are unavoidable. To dispose of these chemical wastes safely, you need to know some general rules for
chemical waste disposal.
Metals should be placed in a container to be recycled.
Nonhazardous, water-soluble chemicals , such as sodium chloride (NaCl) may be discarded in the sink. If the waste is a solid,
dissolve it in water before disposal in the sink.
Hazardous, insoluble chemicals must be placed in a container that is labeled for waste disposal. Your instructor will inform
you if chemical wastes are hazardous and identify the proper waste containers. If you are not sure about the proper disposal
of a substance, ask your instructor: The labels on a waste container should indicate if the contents are hazardous, the name
of the chemical waste, and the date that the container was placed in the lab.
Hazard ratings are on the chemical’s container . The general hazards of a chemical are presented in a spatial arrangement of
numbers with the flammability rating at twelve o’clock, the reactivity rating at the three o’clock position, and the health

"rating at the nine o’clock position. At the six o’clock position, information may be given on the reactivity of the substance
with water. If there is unusual reactivity with water, the symbol W (do not mix with water) is shown. In the laboratory, you
may see these ratings in color with blue for health hazard, red for flammability, and yellow for reactivity hazards.
Flammability (red)
Health (blue) Reactivity (yellow)
Special Hazard (white)
A chemical is assigned a relative hazard rating that ranges from 1 (little hazard) to 4 (extreme hazard). The health hazard
indicates the likelihood that a material will cause injury due to exposure by contact, inhalation, or ingestion. The
flammability hazard indicates the potential for burning. The reactivity hazard indicates the instability of the material by
itself or with water with subsequent release of energy. Special hazards may be included such as W for reactivity with
water or OX for oxidizing properties.
Commitment to Safety in the Laboratory
I have read the laboratory preparation and safety procedures and agree that I will comply with the safety rules by
carrying out the following (check each item):
Read laboratory instructions ahead of lab time.
Know the locations of eyewash fountains, fire extinguishers, safety showers, and exits.
Wear safety goggles or safety glasses in the laboratory at all times.
Use the proper equipment for laboratory procedures.
Never perform unauthorized experiments or work alone in the laboratory.
Remember what is hot if I have used the Bunsen burner or hot plate.