presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Department of Biochemistry October 15th, 2013 Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  It is a requirement to have a spill kit be available in the laboratory area; •  Managable chemical spills should be cleaned up by the laboratory personnel using the available spill control kit. •  To decide if you have a manageable spill, ask yourself: -­‐ Do you know what chemical was spilled? -­‐ Do you have access to a MSDS for the spilled chemical? -­‐ Do you have Personal Protec2ve Equipment to protect yourself from the spill hazards? -­‐ Do you have the necessary materials to clean up the spill? -­‐ Are you trained to use the spill control kit for this chemical? •  If you answered NO to any of the ques2ons above, then you are unprepared to clean-­‐
up. The Environmental Health & Safety Office (EHS) should be contacted immediately for assistance, by calling 214-­‐648-­‐2250. •  EHS has a trained team of emergency responders that will assist in the clean-­‐up. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  A:end to any person(s) who may have been exposed and/or injured if it is safe to reach them. •  Use safety showers and eyewashes as appropriate. •  In the case of eye contact, promptly flush eyes with water for a minimum of 15 minutes and seek medical a:en2on immediately. •  For inges2on cases, contact the Poison Control Center at 1-­‐800-­‐222-­‐1222. •  In case of skin contact, promptly flush the affected area with water and remove any contaminated clothing or jewelry. If symptoms persist a^er washing, seek medical a:en2on. •  No2fy persons in the immediate area about the spill, evacuate all non-­‐essen2al personnel from the spill area and adjoining areas that may be impacted by vapors or a poten2al fire. •  If the spilled material is flammable, turn off all poten2al igni2on sources. Avoid breathing vapors of the spilled materials. Be aware that some materials either have no odors or create olfactory fa2gue, so that you stop smelling the odor very quickly. •  Leave on or establish exhaust ven2la2on if it is safe to do so. Close doors to slow down the spread of odors. •  No2fy EHS (214-­‐648-­‐2250) Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Building Evacua2on Procedures •  Building evacua2on may be necessary if there is a chemical release, fire, explosion, natural disaster, or medical emergency. •  Be aware of the marked exits from your area and building. •  The evacua2on alarm is a loud con2nuous siren or horn. •  To ac2vate the building alarm system, pull the handle on one of the red boxes located in the hallway. If there is a fire, call Dallas Fire and Rescue at 911, give your name, and describe the exact loca2on (building name, building loca2on, and room number) and size of the fire, then call UTPD at 911. •  Whenever the building evacua2on alarm is sounded or when you are ordered to leave by the UTPD, EHS, or emergency response personnel, walk quickly to the nearest marked exit and ask others to do the same. •  Outside, proceed to a clear reassembly area that is at least 150 feet from the affected building. Keep walkways clear for emergency vehicles. •  To the best of your ability and without reentering the building, be available to assist UTPD and EHS in their a:empts to determine that everyone has been evacuated safely. •  An Emergency Command Post will be set up near the emergency site by the emergency responders. Keep clear of the post unless you have important informa2on to report. •  Do not return to the building un2l you are told to do so by the UTPD, EHS, or City of Dallas responders. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  Everyone in the lab is responsible for his or her own safety and for the safety of others. •  Before star2ng any work in the lab, make it a point to become familiar with the procedures and equipment that are to be used. •  Work only with chemical products when you know their flammability, reac2vity, toxicity, safe handling, storage, and emergency procedures. •  If you don't understand or are unclear about something, ask! •  Lab coats gloves and safety glasses are required in laboratories employing chemicals. Never wear shorts, sandals, or open-­‐toed shoes in lab. •  Be aware of dangling jewelry, loose clothing, or long hair that might get caught in equipment. •  Store food and drinks in refrigerators that are designated for that use only. •  Wash your hands frequently throughout the day and before leaving the lab. •  Do not wear lab coats, gloves, or other personal protec2ve clothing out of the lab and into non-­‐lab areas (e.g., the NMR Room, Break Room, Trainee Room, etc). This clothing may have become contaminated and you could spread the contamina2on. •  Contact lenses should not be worn in a lab because chemicals or par2culates can get caught behind them and cause severe damage to the eye. •  Do not work alone in a lab if it is avoidable. If you must work alone, make someone aware of your loca2on and have them call or check on you periodically. Its is strictly forbidden to carry out hazardous experiments alone (see examples of hazardous experiments on the next page). Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. X
Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. X
EXAMPLES OF HAZARDOUS OPERATIONS: •  Any large-­‐scale experiment that is highly exothermic •  Work-­‐ups where large quan22es of acids or bases are neutralized or the evolu2on of gases are expected (e.g., CO2) •  Diazo2za2on •  Prepara2on and reac2ons of diazonium salts (e.g., Balz-­‐Schieman rxn) and organic azides •  Any experiment/reac2on where heavy metal perchlorates are formed •  Friedel-­‐Crajs reac2ons, aroma2c nitra2ons & halogena2ons (HNO3/H2SO4, Cl2) •  Reduc2ons in liquid ammonia (e.g., Lithium metal, sodium metal in NH3) •  Any reac2on where HCN (hydrogen cyanide) or vola2le cyanides are formed or used (e.g., TMSCN, KCN/acid, BrCN/water., etc.) Use a cyanide detector! •  Transi2on-­‐metal catalyzed carbonyla2ons (use CO detector!) •  Any experiment that requires the handling of highly pyrophoric metals and reagents (e.g., tert-­‐butyllithium). •  Quenching of Na, K, Li metal or metal hydrides (NaH, KH, LiAlH4). •  Ozonolysis of alkenes (unreduced ozonides may explode) – check with KI/starch Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Video 1: Gekng Ready •  Using a fume hood •  Using gas cylinders •  Using vacuum and vacuum traps Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  No researcher is permi:ed to carry-­‐out a hazardous opera2on alone in the laboratory. In order for a researcher to conduct a hazardous opera2on, the operator must no2fy one or more laboratory personnel of his/her inten2on to conduct a hazardous opera2on and the details of that opera2on. At least one person must be designated to remain within visible and audible distance throughout the dura2on of the hazardous opera2on. Working alone in the laboratory at any2me is strongly discouraged. Responsibility Of The Next-­‐To-­‐Last Person To Leave The Laboratory •  The penul2mate person to leave the laboratory has a responsibility to no2fy the remaining person that they are leaving. Thus no one should unexpectedly find themselves alone in the laboratory. Responsibility Of The Last Person(s) To Leave The Laboratory •  The last person(s) to leave a laboratory for the day should carry out the following procedures: 1) Walk through the laboratory, inspec2ng for unsafe condi2ons and injured persons. 2) Turn off all equipment and instrumenta2on that can be safely shut down. 3) Ensure that all hood sashes are lowered. 4) Turn off the lights. 6) Close and lock all doors. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  Avoid unnecessary exposure to chemicals by any route. •  Do not smell or taste chemicals. •  Vent apparatus which may discharge toxic chemicals (e.g., vacuum pumps, dis2lla2on columns) into local exhaust devices. •  Do not allow release of toxic substances in cold rooms or warm rooms, since these have contained recirculated atmospheres. •  Do not eat, drink, chew gum, or apply cosme2cs in laboratory areas. Wash hands before conduc2ng these ac2vi2es. Smoking is not allowed in our campus. •  Inspect all glassware before use. Repair or discard any broken, cracked, or chipped glassware. •  Do not allow burners or any other igni2on sources nearby when working with flammable liquids. •  Do not vent the separatory funnel near a flame or any other igni2on source and do not point it at a co-­‐worker or equipment. It is best to vent the separatory funnel into a fume hood. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  The most important thing to remember about protec2ve clothing is that it only protects you if you wear it. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  Full-­‐face shields provide addi2onal protec2on to the face and neck and should be worn when conduc2ng par2cularly hazardous opera2ons. •  Safety glasses or goggles must be used in conjunc2on with a full face shield. •  When possible, a safety shield should be placed around poten2ally dangerous experiments. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Video 2: Transferring Pyrophoric Liquids •  Using Schlenk line for sekng up a reac2on •  Using syringes, needles, and cannulas for tranferring liquids •  Wearing protec2ve gear •  Demonstra2on of the proper use of ter$arty-­‐BuLi Video 3: Working with Reac2ve Metals •  Different types of fire ex2nguishers •  Washing Na metal in different solvents VIDEO 4: PYROPHORICS Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. 1. Complete the S2ll Registra2on Form on the EH&S Website h:p://www.utsouthwestern.edu/utsw/cda/dept145569/files/605683.html Complete the Sodium/ Hydride SAll RegistraAon Form • Ask yourself, “Do I really need to set up this s2ll?” 2. Use Proper Experimental Procedure to Set Up the S2ll • Use the primary literature • Use purifica2on books (e.g., “Purifica2on of Laboratory Chemicals” by Perrin and Armarego) 3. Use Proper Procedure to Quench the S2ll Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Most fires and many injuries in chemistry labs come from improper and/or untrained quenching of s2lls. This is a dangerous process, but can be done safely every 2me if you follow these rules. General consideraAons: • Never do this by yourself for the first 2me. Always ask your colleagues or advisor to help if you have not done it before. • Always do this when others are present. • Always wear eye protec2on, gloves, and a lab coat, and perform all procedures in the hood. • Never dis2ll anything (hydride s2ll or otherwise) to dryness. • Allow several hours to quench the s2ll. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Quenching procedure: • Allow the dis2lla2on apparatus to come to room temperature. Do not use a water or ice bath to cool or at any stage of this procedure. • Make sure there is an appropriately sized s2r bar in the flask. • Place the flask in an empty crystallizing dish (or similar secondary container) on a s2r plate, and be sure the s2r bar is spinning. • No condenser is necessary, and do NOT seal the flask (stopper, etc.). You can use an addi2on funnel with a pressure-­‐equilibra2ng tube if desired. Only use this if you/it are capable of adding one drop at a 2me. • Add isopropanol dropwise. At the beginning, this means 1 drop every 15-­‐30 sec. DO NOT RUSH. You will see vigorous gas evolu2on in the beginning. When gas evolu2on stops, s2r the mixture vigorously for 30 min. This is the most dangerous 2me. O^en people assume everything is quenched, only to find that there were insoluble clumps that cause a problem when they come in contact with water. • A^er s2rring for 30 min, add MeOH dropwise. Use an equal volume as you used IPA. S2r 1h. • Add water dropwise. Use an equal volume as you used IPA and MeOH. S2r 1h. Dispose as mixed aqueous/organic waste. • For sodium sAlls: Follow same procedure as above, but s2r overnight before introduc2on of water. S2r several hours a^er introduc2on of water. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Laboratory Fire Preven2on •  Minimize the use of open flames: Bunsen burners, propane torches. •  Be aware of sparking sources in the laboratory: heat guns, variacs, electric motors. •  Ovens must be elevated from the floor to minimize the risk of fire should a solvent spill. •  Minimize the volume of flammable solvent on-­‐hand at any one 2me. Place smaller solvent orders more frequency. •  Store bulk solvents (containers greater than or equal to 4 L) in flammable material cabinets. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  The two most common types of ex2nguishers in laboratories are pressurized dry chemical (Type BC or ABC) and carbon dioxide (CO2) ex2nguishers. Types of Fires Class A fires are ordinary materials like burning paper, lumber, cardboard, plas2cs etc. Class B fires involve flammable or combus2ble liquids such as gasoline, kerosene, and common organic solvents used in the laboratory. Class C fires involve energized electrical equipment, such as appliances, switches, panel boxes, power tools, hot plates and s2rrers. Water can be a dangerous ex2nguishing medium for class C fires because of the risk of electrical shock unless a specialized water mist ex2nguisher is used. Class D fires involve combus2ble metals, such as magnesium, 2tanium, potassium and sodium as well as pyrophoric organometallic reagents such as alkyllithiums, Grignards and diethylzinc. These materials burn at high temperatures and will react violently with water, air, and/or other chemicals. Handle with care!! Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Dry chemical ex2nguishers are useful for either class ABC or class BC fires (check the label) and are your best all around choice for common fire situa2ons. They have an advantage over CO2 and "clean agent" ex2nguishers in that they leave a blanket of non-­‐
flammable material on the ex2nguished material which reduces the likelihood of reigni2on. They also make a terrible mess -­‐ but if the choice is a fire or a mess, take the mess! Note that there are two kinds of dry chemical ex2nguishers: Type BC fire ex2nguishers contain sodium or potassium bicarbonate (NaHCO3, KHCO3) Type ABC fire ex2nguishers contain ammonium phosphate [ (NH4)3PO4 ]. CO2 (carbon dioxide) ex2nguishers are for class B and C fires. They don't work very well on class A fires because the material usually reignites. CO2 ex2nguishers have an advantage over dry chemical in that they leave behind no harmful residue. That makes carbon dioxide (or Halotron I or FE-­‐36) a good choice for an electrical fire involving a computer or other delicate instrument. Note that CO2 is a bad choice for a flammable metal fires such as Grignard reagents, alkyllithiums and sodium metal because CO2 reacts with these materials. CO2 ex2nguishers are not approved for class D fires! Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. Metal/Sand Ex2nguishers are for flammable metals (class D fires) and work by simply smothering the fire. The most common ex2nguishing agent in this class is sodium chloride, but there are a variety of other op2ons. You should have an approved class D unit if you are working with flammable metals. Sodium chloride (NaCl) works well for metal fires involving magnesium, sodium (spills and in depth), potassium, sodium/potassium alloys, uranium and powdered aluminum. Heat from the fire causes the agent to cake and form a crust that excludes air and dissipates heat. Powdered copper metal (Cu metal) is preferred for fires involving lithium and lithium alloys. Developed in conjunc2on with the U.S. Navy, it is the only known lithium fire figh2ng agent which will cling to a ver2cal surface thus making it the preferred agent on three dimensional and flowing fires. Graphite-­‐based powders are also designed for use on lithium fires. This agent can also be effec2ve on fires involving high-­‐mel2ng metals such as zirconium and 2tanium. Specially-­‐designed sodium bicarbonate-­‐based dry agents can suppress fires with most metal alkyls, pyrophoric liquids which ignite on contact with air, such as triethylaluminum, but do not rely on a standard BC ex2nguisher for this purpose. Sodium carbonate-­‐based dry powders can be used with most Class D fires involving sodium, potassium or sodium/potassium alloys. This agent is recommended where stress corrosion of stainless steel must be kept to an absolute minimum. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. If a fire occurs, researchers do not have to aLempt to exAnguish it. The default acAon should be to call 9-­‐1-­‐1 and pull the building fire alarm. To use a fire exAnguisher: 1.  Pull the pin 2.  Aim at base of fire 3.  Squeeze handle 4.  Spray from side to side Researchers should never a:empt to ex2nguish a large fire or jeopardize their own health or safety to fight a fire. Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D. •  L -­‐-­‐ Label everything clearly •  A -­‐-­‐ Appropriate containers in good condi2on •  B -­‐-­‐ Be neat and orderly •
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S -­‐-­‐ Store only what you will use A -­‐-­‐ Always wear protec2ve clothing F -­‐-­‐ Food allowed in ea2ng areas only E -­‐-­‐ Everything in its place on a shelf T -­‐-­‐ Time to inventory & organize Y -­‐-­‐ Your safety and the safety of others is cri2cal Lecture on Laboratory Safety: Part I. presented by László Kür2, Ph.D. & U:am Tambar, Ph.D.