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Safe Laboratory Practices and Procedures. Chemistry Department University of Cincinnati. Outline. Emergency Procedures Required Procedures Safe Laboratory Practices Chemical Hazard and Risk Information Gas Cylinders Horror Stories Future Safety Plans. Emergency Response Plan.
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Safe Laboratory Practices and Procedures Chemistry Department University of Cincinnati
Outline • Emergency Procedures • Required Procedures • Safe Laboratory Practices • Chemical Hazard and Risk Information • Gas Cylinders • Horror Stories • Future Safety Plans
Emergency Response Plan • All personnel must begin evacuation at once. Pull the manual fire alarm, if building is not already in alarm to alert all occupants. Call 9-1-1 once outside the building. • Take any valuable personal items. • As you leave the laboratory or office, quickly check to determine if all co-workers have begun to evacuate. The last person out should close, but not lock the door to the laboratory. • All personnel must familiarize themselves with the most rapid means of escape from their laboratory or office. Evacuation maps are posted in hallways near the elevators.
An alternative means of escape should also be noted for those emergencies where the first exit is blocked. • Never use the elevators if a fire alarm activates; take the stairs instead. • Once you have evacuated the building, assemble at designated areas to enable safety monitors to ensure everybody has evacuated. • Assemblage areas are outside Crosley Tower on the second floor, outside Reveischl Hall on the fourth floor or the sixth floor. • Designated Safety Monitors (faculty) will ensure their assigned areas are evacuated. • You cannot enter the building until given permission by Emergency Response Personnel.
A. Fire Emergency:Controllable Fire • Pull the manual fire alarm, if building is not already in alarm to alert all occupants. Call 9-1-1 once outside the building. • Notify everyone in the immediate area of the danger. • Non-essential personnel should evacuate the area. • You may fight the fire yourself if: a) You have been trained in the use of fire extinguishers, b) the fire is small (size of a wastebasket) and confined to a specific area (such as a fume hood),c) you are reasonably certain that the fumes that are generated are not toxic d) you have a clear means of escape if the fire proves to be out of your control. • Never turn your back on a fire even if you believe it to be extinguished. • Report the fire to the floor’s Safety Monitor (faculty) and UC Fire Prevention (556-4992) even if extinguished.
A. Fire Emergency:Uncontrollable Fire • Notify everyone in the immediate area of the danger. • Pull the manual fire alarm, if building is not already in alarm to alert all occupants.Call 9-1-1 once outside the building. • Evacuate the area • Close doors and windows if possible • Evacuate the building and go to an assembly area.
B. Persons with Disabilities (Fire) Public Safety guidelines permit individuals with disabilities the option of staying in the building during an emergency situation if they are non-ambulatory, or where elevator assistance is essential for their evacuation, and they are located either above or below the ground floor. A non disabled person should stay with the disabled to assist if necessary. Detailed instructions are available by visiting University of Cincinnati Fire Prevention’s website at http://www.uc.edu/techserv/fireprev.htm. The individual, or a person designated to be with them should: • If on ground floor, exit the building as usual. • If above, or below ground, seek a safe place- preferably a designated area of refuge (none are currently located in Logan Hall), or a room with an exterior window, a telephone, and a solid door. • Telephone Emergency Dispatch (9-1-1) and advise them you are a person with a physical disability. Give your exact location – Building, Floor and Room number and the number of the phone number you are calling from. • The Fire Department will determine if evacuation of these occupants is necessary.
C. Chemical Release:Controllable Chemical Release without Injury or Illness • Stop the release of chemicals if possible and safe to do so. • For flammable material, disconnect all ignition sources. • Notify all personnel in the immediate area of the danger. • Evacuate all non-essential personnel. • Once the chemicals are contained, perform appropriate clean-up procedures. • Clean-up procedures should follow instructions on appropriate kits and in accordance with Material Safety Data Sheets. a)Appropriate protective gear needs to be worn. b)For flammable liquids, Flammable solvents may be absorbed with dry absorbents, such as commercially available universal spill control products, vermiculite or sand. Use spark-free utensils to pick-up the waste. c) For toxic liquids, spill control and clean-up, various dry absorbents may be used. These include commercially available universal spill control products, vermiculite and sand. Waste material must be bagged and tagged for disposal. Store waste in a ventilated area.
d) For corrosive liquids: 1) Small acid spills can be neutralized by applying sodium bicarbonate or a similar weak base, and allowing reaction to occur. The neutralized material can then be swept up and disposed via regular waste disposal or through the sewage system, if the quantity is not large. 2) Small caustic spills can be neutralized by the addition of citric acid, or other similar weak acid. The reacted material can then be swept up and disposed of via regular waste collection or the sewage system, if the quantities are not large. 3) Dry absorbents may also be used on either acidic or basic spills. Materials suitable for use as absorbents include commercially available spill control products, vermiculite, and sand. 4) Hydrofluoric acid spills require special spill control products. Do not use sand or vermiculite. Follow specific guidelines in the Material Safety Data Sheet.
e) For solid chemicals: 1) Nontoxic solids can be swept up (avoiding breathing dust) and disposed of in a waste container. 2) Oxidizers must not contact paper, e.g., trash cans. 3) Toxic or reactive solids must be handled carefully and in accordance with instructions given in Safety Data Sheets. 4) Small mercury spills can be collected using a vacuum device or gathered using an amalgamating powder, e.g., sulfur. The waste needs to be tagged for disposal. Large mercury spills require a Mercury Vacuum Cleaner. f) The waste material needs to be disposed of properly.
C. Chemical Release:Uncontrollable Chemical Release without Injury or Illness • Get away from the area until proper provisions can be made. • Notify personnel in the immediate area of the chemical release. • Pull the manual fire alarm, if building is not already in alarm to alert all occupants.Call 9-1-1 once outside the building. • If the chemical spill is large, in a poorly ventilated area or is extremely toxic (that is, if it is beyond the capabilities of the attending personnel or of the equipment at hand), call 9-1-1 for the HazMat Team for assistance. • Close the door and windows, if possible. • Report the incidence to a Safety Monitor
C. Chemical Release: with Injury or Illness • Follow the Chemical Release Plan. • If you are already in the exposure area, remove the injured person from the area of exposure without injuring yourself. • If you are not initially in the exposure area, do not attempt to remove the victim or enter the exposure area. You may become a victim yourself. • If the situation is life threatening, call 911 immediately. • Begin decontamination by moving the victim under a safety shower or over an eyewash station. Flush contaminated areas thoroughly. • If possible, determine which chemical was released. • Monitor the victim for an extended period of time especially prior to the arrival of medical personnel. Symptoms may take a while to appear. • All injured personnel need to be examined by a doctor before returning to work.
D. In Case of Bomb Threats or Suspicious Activities When you receive a bomb threat or observe a suspicious person or activity: • Notify UC police. Do not use a cell phone to report bomb threats. • Do not attempt to remove or open suspicious packages • Suspicious individuals can be approached; however, do not confront them in a threatening manner.
E. Severe Weather • If severe weather is detected (severe thunderstorms, tornadoes etc) the campus severe weather warning system will sound, instructing all occupants to: • Evacuate your area using either stairwell. Elevators may only be used by individuals with disabilities. • Severe weather safety locations for Crosley Tower are noted as the basement corridor. The public restrooms may also be used as a shelter. • Await further instruction from Public Safety or Cincinnati Fire Department before leaving the assembly area.
Required Procedures YOU MUST: • Wear appropriate eye covering • Wear proper clothing (cotton lab coat and secure shoes) • Not eat or drink in the lab or apply cosmetics, and no food or beverage containers in the lab, empty or otherwise • Always treat reagents as if they are poisonous, toxic, and dangerous • Keep reagent containers sealed and clean (put the receiving date on the container) • Understand the reactivity, toxicity, and hazards of the reagent that you are using (check its MSDS sheet) • Dispose of materials properlyand in a timely manner • Keep the lab clean and uncluttered • Not transfer chemicals in a public elevator; use the dumb waiter • Not become complacent
Safe Laboratory Practices • All procedures involving harmfulchemicals must be done in a fume hood whenever possible. Check the hood with a kimwipe before using it to make sure it is pulling air. • The sash of the fume hood should be positioned as low as possible while maintaining secure handling of the materials. • Appropriate gloves should be worn when handling chemicals. • Open all chemical containers and the shipping boxes in a ventilated hood with sash lowered and the container pointed away from your face. • When removing a septum or stopper from your flask, first open the side that is away from your face (it may be under pressure). • Only heat solutions in open systems (drying tube, Ar environment etc.) unless the container is designed to handle high pressures and a blast shield is used. • No open flames or ignition sources near volatile, flammable materials (acetone, ether, etc.).
Do not use chipped or cracked glassware – dispose of it. • Do not force anything e.g. when opening glassware, pushing glassware through stoppers, removing valves from cylinders. You can lubricate glass joints. • Use appropriately sized syringes to transfer reagents and solvents. • Use a cannula for large volumes. • Syringe locking is likely for moisture sensitive materials. • Ask for help or guidance when doing a new procedure, using a new reagent, or before you start forcing something. • Blast shields should be used when manipulating explosive materials outside the fume hood. Rotoevaporation is a dangerous time for chemicals, which are often being dried and heated. Use a high capacity vacuum pump if a solvent has a high boiling point. • Monitor distillations; do not heat to dryness; do not have the hot plate set to a temperature significantly higher than the boiling point of the solvent. • Add reagents to solvent.
Make sure weigh papers that contained reagents are quenched prior to disposal. • Quench all reactive material prior to disposal (e.g., use t-butanol) • Do not mix reactive materials in waste cans (e.g. no strong oxidizers with waste materials). • When finished with liquid nitrogen traps: remove trap from liquid nitrogen, open the system, turn off pump (liquid O2—boom!). • Make sure you consider heats of mixing when quenching reactions or doing extractions. • Carefully vent separation funnels, pointing them away from your face. • Transfer materials safely (inside and outside the lab). Do not wear gloves in the hallways or elevators, in the main or business office, and so forth. Use the dumbwaiter to transfer harmful materials between floors. • Label containers holding prepared solutions - contents, hazards and concentration. • Do not transport or store NMR tubes in your pockets
Hazard and Risk Information Internet Resources MSDS Directory (http://www.ilpi.com/msds/index.html) National Institute for Occupational Safety and Health (NIOSH) Pocket Guide to Chemical Hazards and International Chemical Safety Cards (http://www.cdc.gov/niosh/npg/npg.html) SAFETY Listserv Archives (http://hazard.com) Sigma Aldrich (http://www.sigmaaldrich.com/united-states.html) MSDS sheets
Gas Cylinders • Compressed gas cylinders have an enormous amount of stored energy just waiting to be released (2200 lbs. p.s.i. stored pressure) • Can be released if they are dropped, mishandled or abused. • If the regulator or valve connection is broken, exhaust vapor under pressure creates a force that moves the cylinder like a jet engine • Damage to property and injury or death to people could easily result when this type of energy is released, not to mention the gas is also released.
Handling Cylinders • Assure all cylinders are properly restrained from tipping and falling against objects. Never have more than 5 cylinders restrained together in one place. Pedestal base, chain or belt restraints all work well. A proper restraint is critical. • Don’t move a cylinder with a regulator attached; have its valve cap in place when moving it. • Never transport cylinders horizontally. Use a cylinder cart with a restraint belt or chain and keep them nearly upright. • Assure the contents of all your cylinders are properly labeled. Know the hazards of the contents by reviewing the Material Safety Data Sheet (MSDS) for each gas you use. • Remember, many gases can cause frostbite upon contact, and may not be smelled or seen. • If you hear vapor escaping, ensure the valve is closed. If you still hear vapor, you may have a leak. A soap bubble solution can help you find a small leak. • Never use grease or oil near oxygen cylinder regulators or valves. Spontaneous ignition could occur.
Horror Stories Accident: Transferring ~ 50 mL t-butyl lithium (in pentane) with a 50 mL syringe Barrel came out of the syringe Flash fire ignited her clothes (sweater) She ran the wrong direction from the safety shower She eventually died from the accident
Better Lab Practice: Use a syringe with a greater capacity than the liquid to be transferred Better to transfer large volumes via a cannula (double headed needle) Operate the syringe in the fume hood with sash as low as possible (arms exposed only) and pull in a direction away from the body Wear a cotton lab coat, which is less likely to catch fire (never wear a lab coat made of synthetics – they melt and burn while stuck to your skin) Know where the safety shower, fire blanket and eye wash are
Accident: Synthesis of an energetic material, most likely nickel hydrazine perchlorate Not supposed to make more than 100 mg of the material, the student synthesized 10 g. Because the product was lumpy, student placed his portion into a mortar. He believed that the compound was safe when “wet,” so he added some hexane and—wearing safety goggles but working at a bench in the middle of the lab, with no blast shield—“very gently, very, very gently” used a pestle to try to break up the chunks, He set down the mortar and took off his goggles. Then he decided to give the compound one last stir. The mortar exploded in his hands. He “lost three digits on his left hand, severely lacerated his right hand,
perforated his left eye, scratched his right eye and had superficial cuts to the parts of his body that were exposed The student’s laboratory notebook provides no detail about what exactly the two were doing in the lab on the day of the incident. During that time, the notebook includes seminar notes, other notes seemingly unrelated to his research, and only vague descriptions of experimental work: One apparent synthesis is documented in an undated entry simply as “Ni(NO3)2 + hydrazine / 10 g / purple ppt forms immediately / also an exothermic rxn.” The other student’s “notebook” is a typed summary of reaction protocols and observations, also without dates.
Interviews with other researchers who worked in the lab indicate that his labmates were disturbed by his conduct in the lab prior to the incident. His space was disorganized, items were not labeled, and “there had been conflicts over work space, cleanliness of the lab and use of chemicals,” Student started scaling up syntheses, first to 1 to 3 g and then to 5 g. The researcher told the student the scale-up was inappropriate; student reportedly responded that things were “just fine.” The researcher apparently did not report the scale-up Student transported as much as “several grams of compounds” at a time in glass vials in a backpack or coat pocket, a researcher who helped the student told EH&S investigators. He “was told that a metal container would be better for the transport, but he continued to bring them in a glass vial,”
Several vials of material were found in the student’s home. The containers were largely unlabeled, except for one marked “TATP,” most likely for triacetone triperoxide. The bomb squad destroyed the items. Student brought vials home from the lab because he absent-mindedly left them in his pockets Other powders and liquids found in the lab could not be identified because of improper labeling.
Better Lab Practice: Wear appropriate eye protection Use blast shields when working with energetic materials The first rule of handling energetic materials is to keep quantities small Do not become complacent because accidents haven’t happened – yet... Let advisor know before scaling up materials Follow safety policies to the letter Transport materials in appropriate containers Write down and follow safe protocols
Accident: Rotoevaporation of a peroxide Student removed flask from bump trap and the flask disappeared in an explosion. Student was not hurt, luckily the glass returned to sand Rotoevaporation of an azide Gram scale reaction was evaporated to dryness and left heating for a long time. The flask exploded Student suffered cuts on his face, chest, and hands
Better Lab Practice: Use a blast shield when using a rotoevaporator with energetic materials Do not heat the solid excessively If possible, just reduce the volume without reaching dryness If possible, manipulate small scales of energetic/reactive materials
Future Safety Plans • Research Group Chemical Hygiene Plan – describes safe practices and procedures appropriate for that group. Appendices – written by group members for particularly harmful materials or procedures. These will be available for all departmental members. • Self Safety Audits – Each group checks for safety violations. • Departmental Safety Audits – Members of the Safety Committee will check for violations • Adding safety questions to research presentations
CHP Appendix Example Piranha Solution Standard Operating Procedure Neil Ayres Research Group Overview: Piranha solution is a powerful oxidizing solution used to remove organic residues from substrates. In this lab, we typically use a 7:3 mixture of concentrated sulfuric acid and 30% hydrogen peroxide to etch silicon wafers. Piranha solutions are extremely energetic and may result in explosion or skin burns if not handled with extreme caution. Any researcher handling piranha should wear a laboratory coat, closed toe shoes, long pants, safety glasses, and neoprene or polyvinyl chloride gloves (nitrile gloves do not supply sufficient protection). Piranha solution must be prepared under the hood with the glass shield pulled down as far as it can go within a comfortable working distance. The solution should be prepared in a glass container-never in plastic. NEVER allow any organic to come in contact with piranha (this will cause an explosion).
Always add the acid SLOWLY to the hydrogen peroxide. After the solution is prepared, begin heating the solution to ~ 70 oC. This should be done SLOWLY in 5-10 degree increments to avoid generating an extreme amount of heat (this reaction is exothermic). Monitor the solution as it is heating, and only increase the temperature when the solution is calm. Always use forceps to insert and remove wafers from the solution. NEVER use your hands. Emergency Procedures: In case of skin contact: May cause skin burns. Remove contaminated clothing and flush the skin with copious amounts of water for at least 15 minutes. Seek medical attention. In case of eye contact: Piranha is corrosive and irritating to the eyes. Flush contaminated eye(s) immediately with copious quantities of water for at least 15 minutes. Seek medical attention immediately. In case of inhalation: May irritate the respiratory tract. Conscious persons should be assisted to an area with fresh, uncontaminated air. Seek medical attention in the event of respiratory irritation, cough, or tightness in the chest. Symptoms may be delayed. In case of ingestion: Not a likely route of exposure.
Storage: Do not store piranha. Mix fresh solution for each use. Disposal: Allow the solution to cool completely before removing it from the hood. Turn on the water in the sink and, using forceps, carefully transport the solution to the sink. With the forceps, dump the solution, and leave the dish to flush under the running water for several minutes before removing.
Summary • You are responsible for laboratory safety • Always treat reagents as if they are poisonous, toxic, and dangerous • Understand the reactivity, toxicity, and hazards of the reagent that you are using (check its MSDS sheet) • Ask for help or guidance when doing a new procedure or working with new materials • You must not become complacent