Technical information

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Choice of chemicals:
• The use of the following five chemicals is illegal in the City of Cambridge, MA, and must not be
brought onto the MIT campus. These chemicals are:
• Soman GD - nerve agent
• Lewisite - blister agent
• Mustard HD - blister agent
• VX - nerve agent
• Sarin GB- nerve agent
• The signature of the principal investigator is required to purchase the following chemicals:
• Ethyl Alcohol (Tax free alcohol)
• Explosives
• Hypodermic Needles and Syringes
• Liquefied Petroleum Gases (LPG)
• Nitrous Oxide Gas
• Poisons
• Before a substance is received, information on proper handling, storage and disposal should be
known by the user. No laboratory chemical should be accepted without a label that identifies the
chemical's name, and an accompanying Material Safety Data Sheet.
• Use only those chemicals and/or quantities of chemicals for which the quality of the available
engineering controls (e.g. chemical hood and ventilation system) is appropriate.
• Assume that all substances of unknown toxicity are toxic and minimize exposure to such
substances as much as possible.
Personal protection:
• All containers must be labeled as to content, composition, and appropriate hazard warning:
flammable, explosive, corrosive, toxic, etc. The laboratory worker's name and the date the
container was filled must be on the label.
• Toxic chemicals will be exposed to the air only in a property ventilated hood. Flammable
chemicals will be exposed to the air only under a properly ventilated hood or in an area which is
adequately ventilated (airborne concentration will be less than the Permissible Exposure Limit
("PEL") specified by the appropriate OSHA standard).
• When airborne concentrations of chemicals are or could be of concern, consult the MIT
Environmental Medical Service.
• The user should keep personal protective items clean. In case the user knows or suspects that the
item has become contaminated, it should be promptly removed and cleaned prior to reuse. Any
skin area that may have become contaminated should be promptly and thoroughly washed.
Use of a Hood:
• A chemical hood should be used for operations which might result in significant release (e.g.
above the OSHA permissible exposure level) of toxic chemical gases, vapors or dusts.
• As a rule of thumb, consider the use of a hood or other local ventilation device when working with
any appreciably volatile substance of unknown toxicity or with an airborne occupational exposure
limit below 50 parts per million (ppm).
• Adequate hood performance should be confirmed before use. This can be done by checking the
Vaneometer, warning light or checking with a piece of tissue. For the best chemical hood
performance the user should keep the work area five or six inches behind the plane of the sash,
keep the hood sash closed except when adjustments within the hood are being made, keep
materials stored in hoods to a minimum and not allow such items to block or interfere with
airflow. If you suspect that the hood is not working properly, contact Physical Plant (phone
FIXIT).
• The hood should be kept "on" with the sash down when it is not in active use if toxic substances
are stored in it, or if it is uncertain whether adequate general laboratory ventilation will be
maintained when it is "off."