Chemistry Laboratory Safety Checklist - Safety CC5 Chem 2A/2B/5/14/16/20    

You are required to read and initial each of the following. Ask your instructor to clarify any points you do not understand. ______

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Distraction-free environment: • Use of personal electronics (phones, tablets, iPods, laptop computers) is forbidden, except as necessary for recording lab data; • Smoking, eating, drinking, or applying cosmetics are not allowed in the lab. • Understand the hazards of each experiment before you begin work. Housekeeping: • The desk top should be kept free of unnecessary equipment, notebooks, textbooks, etc.; • Walkways and aisles should be kept clear. Backpacks and coats should be stored in the knee-space or at the front of the room; • Stools should be pushed into the knee-space when not actually being sat upon; • Locker drawers should be closed when not being used; • All reagent bottles are to be capped or closed and returned to their proper place when not in use. Unused material must be placed into a proper disposal container; • Wash hands frequently while working with chemical substances. Always wash your hands before handling food or cosmetics, and before using the toilet; • Clean up all spills promptly. Major spills of acids or bases are to be reported immediately to the instructor; • Label all containers of chemicals to be stored in your locker. Include a description of the contents and a page reference to your lab notebook; • At the end of each lab period, clear your counter-top and wipe with a damp paper towel. Protective clothing: • Eye protection is required at all times chemicals are in use. Safety goggles must be worn at all times. “Safety glasses” are not acceptable; • It is not advisable to wear contact lenses in the lab; • Gloves should be worn when handling toxic or corrosive materials; • Additional personal protective equipment (lab coat or apron) may be worn as needed at the student’s discretion. Dress code: • “Neck to knees” body coverage is strongly recommended. “Daisy Dukes” or tops subject to wardrobe malfunctions are not appropriate; • Overly tight or loose clothing should be avoided. You should be able to move freely. You should not have to pull up your pants before walking; • Non-porous shoes that cover the instep are required. Bare feet, flip-flops, sandals and/or open-toed or woven leather shoes are not acceptable; • Long hair should be tied back or otherwise confined. Long beards must be 1  

confined when flames are in use. 5 Emergency Procedures: • “When in danger, when in doubt …” a student’s first responsibility is to assure his or her own safety. Only then assess whether you are capable of rendering assistance to others; • Lab partners should have each other’s back. In case of an accident, you should assist your partner if you can safely do so; • The campus emergency phone number is 911. This number may be used to report fires, summon an ambulance or the police. In case of fire, the first student through any door should pull the alarm; • Know the location and how to use the fire extinguisher, fire blanket, eyewash fountain, and safety shower for your lab. 6 Make-up labs: Written permission is needed to be in the laboratory at times other than your regularly scheduled lab. Even with written permission, there must be at least two students in the laboratory and an instructor must be present or within calling distance.

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Students are required to read the following sections, which detail potential hazards and means of avoiding these or dealing with them if they occur. Students have a positive duty to learn to work safely in the laboratory. Hazards Warning

 

CAUTION -- The solids, liquids and gaseous substances, and combinations thereof, used in experiments are potentially hazardous in one or more of the following ways: •

 

 

They may be irritants to, or have caustic action on, the skin, mucous membranes, lungs, and eyes, may be systemic poisons, and may be flammable or explosive.

Origin of hazards: Unexpected and possibly dangerous situations can result from one or more of the following: • incorrect transfer and handling procedures. • incorrect reaction temperatures. • using incorrect amounts of chemicals. • incorrect order of addition of two or more substances. • incorrect rate of addition of two or more substances • using one or more incorrect substances. • incorrect disposal of chemicals. • incorrect dilution of concentrated acids (Reminder: acids are ALWAYS added to water slowly, carefully, with stirring). Safety and Accident Prevention The following precepts are intended to help you fulfill this additional responsibility: • Always wear eye protection when you or others nearby are working with chemicals or apparatus.

 

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Know beforehand the hazardous characteristics of the chemicals with which you plan to work. Wear chemically resistant lab coats or aprons, not shorts, cutoffs, or miniskirts. Do not wear high-heeled shoes, open-toed shoes, sandals, or shoes made of woven material. Confine long hair and loose clothing. Always wash your hands and arms with soap and water before leaving the laboratory, even if you wore gloves, most especially on trips to the lavatory Never work alone in the laboratory. Do not prepare or store (even temporarily) food or beverages in a chemical laboratory. Never consume any food or beverage when you are in a chemical laboratory. Do not chew gum or tobacco, and do not smoke or apply cosmetics in the laboratory; cosmetics and tobacco products in opened packages can absorb chemical vapors. Never wear or bring lab aprons or lab coats or jackets into areas where food is consumed. Never pipet by mouth; always use a pipet aid or suction bulb Do not handle contact lenses in the laboratory except to remove them when an emergency requires the use of the eyewash fountain or safety shower. Never perform unauthorized experiments. When moving about in the laboratory, anticipate sudden backing up or changes in direction by others. If you stumble or fall while carrying glassware or chemicals, try to project them away from yourself and others. Never remove chemicals from the laboratory without proper authorization. Keep chemicals and apparatus well away from the edges of your laboratory bench or other workspace. Never engage in horseplay, pranks, or other acts of mischief in the laboratory. Report violations of your laboratory’s safety rules to your instructor - you could save their lives - and your own.

Recommended Laboratory Techniques for Work with Chemicals and Apparatus Following these recommendations will help make your work easier and equipment use safer: • Plan your work before starting a laboratory procedure. Be sure you know what to do if you or another laboratory worker has an accident. • Keep your workspace free of clutter. • Set up clean, dry apparatus, firmly clamped and away from the edge of the lab bench, paying attention to the proximity of reagent bottles to burners and to other workers and their equipment. Choose sizes that can properly accommodate the operation to be performed, allowing at least 20% free space. • Except for glass tubing, stirring rods, and graduates, use borosilicate glassware (e.g., Pyrex). Examine your glassware closely for flaws such as cracks and chips. Damaged glassware must be repaired (see your instructor) or discarded in a waste container labeled for broken glass. • Other equipment must be free of flaws such as cracks, chips, frayed wire, and obvious defects. Check with your instructor if you have questions. • A properly placed pan under a reaction vessel or container will act as a secondary containment to confine spilled liquids in the event of glass breakage. • Use shields when working with reactive mixtures. Place the shields in suitable positions to protect yourself and others. Be sure that the shields are stabilized with weights or fasteners so that they cannot be knocked over. Also wear both eye and face protection when using shields. • When working with flammable gases or liquids: • Do not allow burners or other ignition sources in the vicinity unless your instructor directs otherwise. • Use appropriate traps, condensers, or scrubbers to minimize release of material to the  

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environment. If you will be using a hot plate or heating mantle, do not proceed with your laboratory work until you know the autoignition temperatures of the chemicals likely to be released and can ensure that the temperatures of all exposed surfaces are less than those autoignition temperatures. • Make certain that the temperature control device and the stirring/ventilating motor (if present) do not spark. Whenever possible, use an enclosed, non-sparking electric heater or hot plate or use steam in place of a gas burner. Use only non-sparking motors (e.g., air motors) in the chemical laboratory when flammable materials are present. Support and orient large separatory funnels so that the stopcock will not be loosened by gravity. Use retainer rings on stopcock plugs. Use securely positioned clamps to support condensers; secure attached water hoses with wire or clamps, when available. Secure stirrer motors and vessels firmly to maintain proper alignment. Magnetic stirring is preferable, except for viscous materials. Position apparatus that is attached to a ring stand so that the center of gravity of the system is over the base and not to one side. Arrange the apparatus so that burners and baths can be removed quickly. Standards bearing heavy loads must be firmly attached to the bench top. Anchor equipment racks securely at both the top and the bottom. Never place any apparatus, equipment, boxes (empty or filled), containers of chemicals, or any other objects on the floor. Never heat a closed container. Make sure the heating apparatus has a vent. Before you heat more than a few milliliters of a liquid in an unstirred vessel, add some boiling chips or a short glass tube with one end closed. If, as in some distillations, there is the possibility of a dangerous exothermic reaction or decomposition, use a thermometer with its bulb in the liquid. This will provide a warning and may allow time to remove the heat and apply external cooling. Laboratory hoods are recommended for all operations in which toxic or flammable vapors are evolved. Most flammable vapors have a density greater than that of air and will settle on a bench top or floor where they may diffuse to a distant burner or other ignition source and “flash back.” That is, if the flammable vapors are not controlled within a hood, for example - they can evolve, expanding up and out over the containing vessel rim. Then they can travel undetected at floor level over astonishingly long distances. If there is a source of ignition at that distant point, the train of vapor will instantly flash back all the way to the container and either ignite the liquid in the container or cause the vapors near the container to explode. Use a laboratory hood when working with a system under reduced pressure (which may implode). Close the sash of the hood to provide a shield. Note that, unless designed and built for the purpose, hoods are not to be relied on for protection in case of an explosion. •

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At all times, utilize best available practice in the laboratory: • • • •

 

Practice the habit of accident prevention; Use the smallest quantity of material necessary to accomplish the goal of the experiment; When possible, substitute a less hazardous chemical for a more hazardous one; and Anticipate the possible consequences of all work you do in the laboratory.

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Chemistry Laboratory Safety Checklist - Safety CC5 Chem 2A/2B/5/14/16/20  

 

Acknowledgement: Read and initial the following statements, and sign and date the safety contract. Return the contract to your instructor at the beginning of the second laboratory session. Retain pages 1- 4 for your notebook. ______

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1 I have read and I understand the provisions of paragraphs 1 - 6 on pages 1 and 2 of the safety checklist. These provisions were reviewed in class with the instructor and all my questions were answered. I have separately initialed each of those paragraphs. 2 I have read and I understand the provisions of the sections concerning laboratory hazards, accident prevention, and laboratory practices on pages 2 - 4 of the safety checklist. 3 I understand and agree that it is my responsibility to review the safety measures and laboratory practices throughout the course, and to adopt new practices and procedures as required by the experiments I will do. 4 I understand and agree that my failure to follow safe practices in the laboratory is sufficient cause for the instructor 1) to lower my score on specific experiments; 2) to eject me from the laboratory for negligent behavior; and/or 3) to dismiss me from the course with a failing grade for repeated, negligent behavior.

Signature

 

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___________________ Date