University of Massachusetts at AmherstDepartment of ChemistryUndergraduate Organic and Inorganic LaboratoriesLaboratory Safety and Waste DisposalRead this handout carefully, save it, and refer to it throughout the semester.The organic chemistry laboratory is a potentially hazardous work environment, much more so than the generalchemistry lab. The chemicals used in the organic lab are generally more toxic and flammable than those you'veencountered previously. Extreme caution and common sense must be exercised at all times. THINK BEFOREYOU ACT. If you are uncertain about anything, ask a Teaching Assistant or faculty supervisor. Be cognizant ofwhat others are doing around you. Pay close attention to what you are doing. Carefully read the followingcomments on safety and waste disposal as well as the sections on laboratory safety and waste disposal in yourlab text. FAILURE TO FOLLOW THE SAFETY RULES ENDANGERS ALL PERSONS PRESENT ANDWILL RESULT IN THE LOSS OF CREDIT OR EXPULSION FROM THE COURSE.GOOD PREPARATION is a key to safe experimentation. To ensure that you are well prepared, before youmay begin work, you must present an acceptable prelab outline to your TA at the beginning of your lab period.This will constitute 20% of your lab report grade. Note that you will not be allowed to work until you presentan acceptable prelab outline to your TA (see "Notebook and Grading Policies” handout for details.)EYE PROTECTION: Eyes are extremely vulnerable. The possibility of fire, explosion, and the spattering ofcorrosive chemicals makes the wearing of APPROVED EYE PROTECTION MANDATORY. From the momentthat you enter the lab to the time that you leave, you will wear approved eye protection AT ALL TIMES.Whether you are washing glassware, taking a melting point (mp) or spectrum, or weighing material, you willwear eye protection AT ALL TIMES while in the lab. You may be doing something seemingly nonhazardous, butyour neighbor may have an accident that will affect you. For this reason, everyone must wear eye protectionconstantly while in the lab. Failure to do so will result in the loss of credit. Normal prescription glasses are notacceptable. Shatterproof goggles or safety glasses which cover the sides and tops of the eyes must be worn.Safety glasses must conform to ANSI Standard Z87. So called "visitor" glasses are not acceptable. Contactlenses, even with additional safety glasses, should never be worn in the lab. Chemicals splashed into the eyecan become trapped between the eye and the contact lens, making washing of the contaminated spot difficult,and possibly causing the lens to become fused to the eye. If a chemical enters the eye, immediately flush theeye with water for 15 minutes, using an eyewash fountain. Have someone help you to get to the fountain andto keep the eye open while flushing. Report the accident immediately to your instructor. You must beaccompanied to the infirmary as soon as possible after flushing the eye. Know the location of the nearesteyewash fountain.TOXICITY: Treat all laboratory chemicals as if they are toxic - most of them are. Do not inhale them, ingestthem, or allow them to come into contact with your skin. Many organic chemicals can pass rapidly through theskin and even gloves to cause systemic poisoning. Wash spills off of the skin immediately with copiousamounts of water and soap, then consult your instructor. Evaporate hazardous solvents and carry outreactions which emit toxic vapors in a fume hood only. Dispose of wastes properly (see WASTE DISPOSALbelow). For obvious reasons, food and drink, even if in a closed container, are not allowed in the lab. Wash yourhands thoroughly with soap and water before leaving the lab, whether for a moment or for the day.FIRES: Many organic solvents are extremely flammable - more so even than gasoline. For this reason, on theoccasion that a gas burner must be used, before you even think about lighting the burner, be sure that yourTA has given you explicit instructions to do so, and then observe your immediate vicinity to see what yourneighbors are doing. Only when you are certain that no flammable solvents are being used, may you light theburner. Conversely, be certain that no flames are present nearby when you work with a flammable solvent.When finished using a gas burner, always turn off the gas by closing the main valve completely to the downposition. Note that the commonly used solvent, diethyl ether, has an autoignition point of 175°C - even a hotplate or mp apparatus can ignite it. Note too that any electrical device can arc upon being switched on or off,and can therefore ignite a flammable solvent. Be sure that you know the location and proper use of thenearest fire extinguisher and safety shower.ACCIDENTS AND EMERGENCIES: Take careful note of the location and direction for use of all emergencyequipment - fire extinguishers, safety showers, eyewash fountains and first aid cabinets. Minor cuts andthermal and chemical burns are the most common injuries that occur in the lab. The pain and tissue damagefrom minor thermal burns is greatly reduced by cooling the burned tissue IMMEDIATELY with very cold water -the sooner, the better. Use cold tap water immediately, then place the burned tissue in an ice/water bath untilthe pain subsides. Washing immediately with water, then soap and water, is also the first step to take in caseof skin contact with a chemical. A minor scratch can be rinsed out with water and covered with a bandage.Forcing thermometers and glass tubing through an aperture will almost always result in a cut, possibly serious.Twist and push the tubing gently through the aperture, holding the tubing as close to the aperture as possible.If excessive force is required, stop what you are doing and lubricate the tubing with water or glycerol. If aserious injury occurs, an instructor must accompany the injured student to the infirmary. If the injured personcannot be moved, 911 must be called and the location, nature and severity of the injury described.CHEMICAL SPILLS: Clean up spills immediately. Never leave them unattended. If the spill is left, anotherperson may accidentally become contaminated and poisoned. Large spills must be reported to your instructor.(Mercury (Hg) spills, which occur most commonly from broken thermometers, pose a special hazard. Hg has avapor pressure which is high enough to form toxic concentrations in the air.