Technical information

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Waste Disposal:
• A label indicating "Chemical Waste" with the chemical name and concentration should be placed
on each container of chemical waste by the user.
• The MIT Safety Office should be called to collect such chemical wastes and for answers to
chemical waste disposal questions.
• Do not discharge to the sewer flammable liquids, acids or bases (unless the pH has been adjusted
to a range from 6 to 10 and heavy metals are not present), toxic, malodorous, or lachrymatory
substances or any substances which might interfere with the biological activity of the wastewater
treatment plant, create fire or explosive hazards, cause structural damage or obstruct flow.
Protective Clothing and Equipment
• The Laboratory Supervisor will determine the type of personal protection needed in specific
laboratories. The requirements will be posted clearly, and workers will be diligent in adhering to
the guidelines.
• Eye protection worn when working with chemicals should meet the requirements of the American
National Standards Institute (ANSI) Z87.1. This means that chemical safety goggles available
from the Warehouse should be worn whenever there is a potential for chemical contact such as a
liquid splash. When working with more than 10 ml of a corrosive liquid, a face shield should also
be worn. Covering safety eyewear is equally important to the wearer of contact lenses.
Additionally, employees are encouraged to inform their supervisors when contact lenses are worn,
and medical personnel treating the individual in case of chemical contact, so that proper eye
irrigation can be provided. For general laboratory work without the potential for chemical contact
or splash, the routine use of goggles or safety glasses with side shields should be considered.
• When working with corrosive liquids, gloves made of a material known to be resistant to
permeation and degradation from the corrosive chemical should be worn. For example, a neoprene
glove provides excellent resistance against 10% nitric acid while an industrial latex glove provides
only good resistance. With 70% nitric acid the same neoprene glove provides only good resistance
and the use of an industrial latex glove is not recommended by the manufacturer. The MIT Safety
Office can provide additional information on the chemical resistance provided by different gloves
and protective clothing items.
• A laboratory coat should be worn when conducting laboratory activities when contamination is
possible in order to reduce the potential for chemical contact and to protect street clothing. When
significant potential for liquid contact exists the use of safety goggles, impervious gloves and an
impervious apron over the laboratory coat should be considered.
• When working with allergenic, sensitizing, or toxic chemicals, gloves should be worn that are
resistant to permeation by the chemical and inspected by the user for the absence of pin holes.
• Whenever exposure by inhalation is likely to exceed the airborne limits described in the Material
Safety Data Sheet (MSDS) a chemical hood should be used; if this is not possible consult with
your supervisor and/or the Environmental Health and Safety Office before doing any such work.
• Carefully inspect all protective equipment before using. Do not use defective protective
equipment. Keep protective equipment clean.
• Laboratory users should ensure that they have in their laboratory an eyewash unit connected to the
potable water supply. This eyewash unit should be operated periodically (at least quarterly) by the
user to verify proper operation. Keep electrical wires/equipment away from t he area of the
eyewash.
• Laboratory users should know the location of the nearest emergency shower.
Housekeeping
• Access to emergency equipment, showers, eyewashes, and exits should never be blocked by
anything, not even a temporarily parked chemical, housekeeping or maintenance type cart and/or
construction material.
• Original labels on containers of chemicals must be protected so that the identity of the contents
and the hazards those contents present is known. When chemicals are transferred from the original
container to a secondary container, a new label should be attached that shows the chemical