Lab Safety Orientation copied from lab manual PDF

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LABORATORY SAFETY ORIENTATION A chemistry laboratory is a potentially dangerous place in which to work. However, if you are aware of the potential hazards, this danger can be minimized. To this end, specific hazards associated with each experiment are given in the Safety Considerations section of each experiment. Also, by following the laboratory safety regulations printed on the inside front cover of this manual you will minimize the potential for an accident in the laboratory. Should an accident occur, however, immediate treatment can minimize the trauma resulting from the accident. Although the Teaching Assistants are trained to handle laboratory accidents and should be the person to provide first aid, you should also be aware of the proper procedures to be followed in case of an accident. These procedures and the proper use of safety equipment are discussed below.

SAFETY EQUIPMENT EYEWASH The eyewash flushes irritating chemicals from the eyes. Determine the location of the eyewash facility nearest your work station. If you get any chemical in your eyes, go immediately to the eyewash fountain and wash your eyes for at least a full 5 minutes. During this process, keep your eyes open. Obtain prompt medical attention, regardless of the severity of the injury.

A. Eyewash Fountain: off.

B. Eyewahs Fountain: on 1

C. Eyes are not close enough to remove

D. You must fully insert eyes directly in the path of

chemicals from the eye.

the stream and you must use your fingers to forcefully keep your eyes open during the flush.

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SAFETY SHOWER The safety shower has two purposes: to extinguish clothing fires and to provide a whole body wash in the case of large chemical spills.

E. Safety Shower with Curtain. Notice that there is also an eye wash station near the shower.

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Clothing Fires: If your clothing catches on fire, it is natural response to panic and run. Do not do this, since this will simply fan the flames and make it worse. The first response is to drop-and-roll to smother the flames; however, if you are close to a tap you can douse with water as a first response or if you are close to a shower you can immerse yourself in the shower as a first response. Furthermore, if you are not close to a tap or shower, you must drop-and-roll to smother the flames and the lab instructor (TA) or any willing person will bring a fire blanket to further help extinguish the flames and/or they will help you to the closest shower if necessary.

After the clothing fire is extinguished, remove contaminated clothing carefully to avoid further damage to the burned area. Remove heat with cool water or ice packs until tissue around burn feels normal to the touch. The injured person should be covered to prevent shock. Get medical attention immediately by calling 9-911 and campus safety. Small Chemical Spills: A small chemical spill of hazardous chemicals such as strong acids or bases on exposed skin must be immediately washed away by placing affected area under a cold tap of running water until all residual chemicals have been remove (a minimum of 5 minutes). Large Chemical Spills: A large chemical spill of hazardous chemicals such as strong acids or bases on exposed skin or clothing must be immediately washed away under the safety shower. If chemical spill is on clothing which is directly in contact with your skin then you must also remove that clothing whilst in the safety shower. You may make use of the shower curtain to protect your modesty. If necessary, there is also a safety shower in the first aid room on ground floor Spinks which provides total privacy.

FIRE EXTINGUISHERS In the laboratory you will sometimes be working with flammable chemicals. If a fire should occur, extinguish all nearby burners and remove combustible materials and solvents from the area. Small, contained fires in flasks and beakers are extinguished by covering the container with a larger beaker, or a watch glass. If the fire is not contained or threatens to spread, extinguish the fire with a dry chemical fire extinguisher by directing the nozzle at the base of the flames. Do not use water on chemical fires.

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Important: Once you have emptied the fire extinguisher and the fire is still not extinguished. You must sounds the alarm and vacate the building; this fire is now the responsibility of the professional fire department who will safely extinguish the fire. Do not run around looking for another fire extinguisher to put out the flames since this will put your life at risk. If emptying the first fire extinguisher was not enough to kill the flames, it is obvious that the fire is already out of control and is now an immediate hazard to your wellbeing and of course life.

F. Fire Extinguisher and Fire Alarm Lever.

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FUME HOODS In our labs, all the procedures will be carried out in the fume hood. The sashes should be kept at the minimum necessary opening. Refer to Appendix H for more information on the fume hood.

G. Fumehood with protective sash.

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FIRST AID KITS First aid kits are used for minor injuries. Report all cuts and burns to your Teaching Assistant who will apply first aid and help you decide whether further medical treatment is necessary or not.

H. First Aid Kits.

Cuts: For minor cuts, wash the cut with water and remove any pieces of glass or chemical residue before applying a bandage. For major cuts where blood is spurting, place a pad directly on the wound and apply firm pressure. Get immediate medical attention.

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Burns: Immediately immerse the burned area in cold water or ice water for about 5 minutes to reduce the magnitude of the injury.

PERSONAL PROTECTIVE EQUIPMENT

SAFETY GLASSES Approved safety glasses must be worn from the time the laboratory begins until the time you leave the laboratory. There are no exceptions to this regulation. Even if you are not carrying out an experiment, a person near you might have an accident that would endanger your eyes. Even washing dishes can be potentially hazardous.

Cases are recorded where a person has been cleaning glassware and an

undetected piece of reactive material has exploded on contact with the water and sent glass fragments into the person’s eyes. Contact lenses should not be worn in the laboratory, even when safety glasses are worn over them. Contact lenses can trap chemicals against the eye, making it difficult to wash the eye. Soft contact lenses present an additional hazard because they can absorb harmful chemical vapors. I. Lab Safety Glasses

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J. Lab Safety Glasses with side protection.

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L AB COATS Lab coats provide protection against minor chemical spills and can be removed quickly in case of fire or chemical contamination. They should be made of cotton rather than synthetic materials. During a clothing fire, synthetic materials will melt and increase the severity of the burn. Synthetics tend to be dissolved by organic solvents. Lab coats are mandatory.

K. Lab Coat.

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SHOES Proper footwear should completely cover the foot. Do not wear sandals or open-toe shoes in the laboratory.

L. Correct shoe protocol.

M. Incorrect shoe protocol.

HAIR Long hair can be hazardous in the chemistry laboratory. If you have long hair, it is safe and advisable to tie it up or plait and tie it up. (Hair below the shoulder level is considered long).

GLOVES Wear gloves when handling toxic or corrosive chemicals. They should fit the hands snugly and have a non-slip surface. If disposable gloves are used, they should not be re-used.

N. An example of Disposable Lab Gloves.

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GOOD LABORATORY PRACTICE

FOOD OR DRINK IN THE L ABORATORY Do not bring food and drink into the laboratory. They can become contaminated with chemicals by absorption from the air or bench top or by transfer from the hands.

CLEANLINESS In the laboratory you are exposed to a variety of chemicals, all of which are toxic or corrosive to some degree. To minimize personal contamination, keep your bench top clean and wipe up any spilled chemicals as soon as possible. You are handling chemicals during the experiments and so your hands and your fingernails can become quite contaminated. To avoid spreading the chemicals from your hands to your face, eyes, mouth, etc., you should immediately wash off any chemicals accidentally spilled on your hands, and at the end of the lab period, wash your hands before you leave the laboratory.

ELECTRONIC DEVICES All electronic devices such as cell phones, Blackberries, PDAs, iPods etc., must be turned off and stored in your backpacks. You cannot bring them into the lab. Aside from the calculators use of any other electronic device is prohibited during the lab session.

SAFE HANDLING OF EQUIPMENT

BUNSEN BURNERS Bunsen burners provide a convenient and instant source of high temperature [up to 1,100 C]. However, the open flame is an ignition hazard, particularly in an organic chemistry laboratory where flammable solvents are often present. Use care with open flames in the laboratory. Before you use an open flame, check to see if anyone around you is using a flammable solvent.

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O. Bunsen Burner

P. Electric Hot Plate

HEAT SOURCES To minimize the opportunities for fires, use a hot plate, a steam bath, an electric heater, or sand bath when heating reaction mixtures.

Hotplate: This device can be used for both heating and stirring by adjusting the two different control knobs. The hotplate can be used directly for heating aqueous solutions but not for organic solutions. Do not turn the hotplate to the highest setting, and never heat flammable solvents in an open container on the hotplate. Sand bath: The sand bath is another device for heating reaction mixtures. A crystallizing dish filled with 1.0 – 1.5 cm of sand serves as the sand bath. A thermometer is inserted in the sand with the bulb completely submerged in the sand. Either by lowering or raising the vessel to different depths in the sand 13

or by changing the heat supplied by the hotplate, one can closely control the heating of the reaction vessel. Sand contained in the crystallizing dish should not be heated above 200 °C.

Water Bath: When a temperature of less than 100 °C is needed, a water bath is used. Either a copper water bath, a crystallizing dish or a beaker containing water can be used for this purpose. Always use a thermometer to read the temperature of the bath. Clamp the thermometer in such a way that the bulb is inserted in the water, but not touching the container.

Q. Sand bath on hotplate.

R. Hot water bath on hotplate.

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SAFE HANDLING OF CHEMICALS

THE HAZARDS OF ORGANIC SOLVENTS The first thing to remember about organic solvents is that many are flammable and will burn if they are exposed to an open flame or heat source. The second thing to remember is that many are toxic. For example, many chlorocarbon solvents, when accumulated in the body, cause liver deterioration similar to the cirrhosis caused by the excessive use of ethanol. The body does not rid itself easily of chlorocarbons nor does it de-toxify them, therefore, they build up over a period of time and can eventually cause serious medical problems. Many other solvents, such as chloroform and ether, are good anesthetics and will cause drowsiness and then nausea. Pyridine causes temporary impotence. In other words, organic solvents are just as dangerous as corrosive chemicals, such as sulfuric acid, but manifest their hazardous nature in other more subtle, ways. Minimize your direct exposure to solvents. Do not sniff a chemical because it has a nice odor, and do not spill it on yourself. One sensible precaution is to wear gloves when working with organic solvents. In this laboratory, all suspected carcinogens [cancer causing chemicals] have been eliminated and highly toxic or highly flammable solvents are used only when absolutely necessary to perform a particular procedure. Any special precautions required when handling these chemicals are noted in the Safety Considerations section of each experiment. If you are pregnant, you may want to consider taking this chemistry course at a later time. Some exposure to organic fumes is inevitable, and, for most organic chemicals, the minimum exposure levels that present a risk to the development of an unborn child are not known.

USING CHEMICAL REAGENTS To minimize personal exposure to chemicals while performing an experiment you should take only the quantity of reagent required from the stock bottle. In many cases, reagent bottles are equipped with pumps that dispense the required amount. If you must manually remove the reagents from the bottles, you should replace the stoppers or caps after use. Do not remove any stock reagent bottle from the fume hood and do not take a stock reagent bottle to your bench. Stock reagent bottles are to remain in the fume hood to prevent chemical vapors from entering the laboratory environment. To prevent contamination of the stock reagents, never return unused chemicals to the stock bottle. Dispose of any excess reagents in the appropriate waste container.

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W ASTE DISPOSAL Dispose of wastes in the following manner: Dispose of broken glassware in the container specifically designated for broken glassware. Dispose of paper in the waste-paper bins provided in the laboratory. Dispose of solid chemicals in the appropriately labeled waste containers. Dispose of organic liquid chemicals in the appropriately labeled container. Dispose of strong inorganic acids and bases [HCl, H2SO4 and NaOH, KOH] by neutralizing them, diluting them with water, and then pouring them down the sink.

FIRE A LARM If the fire alarm sounds during your laboratory period: Unplug all electrical equipment and turn off all Bunsen burners. Evacuate the laboratory and proceed in a calm and orderly fashion to the assigned emergency exit. The exit for your laboratory room is posted in the laboratory. Do not return to the building until your Teaching Assistant tells you it is safe to do so.

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WORKPLACE HAZARDOUS MATERIAL INFORMATION SYSTEM (WHMIS) The Department of Chemistry is committed to providing a safe, healthy laboratory environment. As a natural consequence, the Department of Chemistry is an active participant in Health, Safety, and Environment programs developed by the University of Saskatchewan. In Canada, safety in the workplace, including student laboratories, is regulated by federal and provincial law, the Canada Labor Code, and the Provincial Occupational Health and Safety Act. Facilities and procedures used in the Chemistry 250.3 laboratory course meet or exceed the standards specified in these acts. Compliance to federal and provincial law in the use of chemical and biological substances requires that employers implement the Workplace Hazardous Materials Information System [WHMIS], by which materials are classified according to specific criteria relating to toxicity, flammability, danger of explosion, etc. Symbols have been developed for each class of hazardous substance to allow for their rapid visual identification. These symbols and the properties of the materials they represent are shown on the back inside cover of this manual. The properties of each controlled biological, and chemical substance used in the workplace are described on a Material Safety Data Sheet [MSDS]. These MSDSs are compiled and made available for inspection by any person who wants to know the properties of the materials with which they will work. MSDSs are available at Chemistry Stores in this building and also at the following sites online. https://www.msdsonline.com/msds-search http://www.msds.com/ You should develop a habit of looking at the MSDS sheets for the chemicals that you will be working with to familiarize yourself with the properties and safety precautions that must be taken when working with them. The existence of laws and information concerning potentially hazardous substances does not, of itself, make a laboratory or any other workplace safe. Safety is the responsibility of each and every individual in the workplace.

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