The safety of yourself and your classmates is of paramount importance during laboratory. Safety regulations must always be observed as it only takes one accident to cause blindness or serious permanent injury. Safety glasses must be worn at all times. After the first day of lab ten points will be deduced if you come to lab without your safety glasses. If you remove your safety glasses when lab is being conducted your instructor will give you a verbal warning once, the second time 10 points will be deduced, and a third offense will result in your being asked to leave the lab.
In the laboratory the chemist works with many potentially dangerous substances and equipment. Yet, with constant alertness, awareness of potential hazards, and some common-sense precautions, laboratory operations can be carried out with a high degree of safety. The most general rules for safety laboratory operations are: be alert - stay alert, and take the trouble to understand what you are doing and the potential hazards associated with the operation you are performing.
Some basic rules and precautions are:
1. Always wear safety glasses to protect your eyes from chemicals and broken glassware.
2. Shoe covering the tops of your feet must be worn at all times while in the lab (flip-flops, sandals, etc. will not do).
3. Never work alone in the laboratory - someone should be in the room with you at all times.
4. Use fume-hood when working with poisonous or offensive gases/fumes, likewise when working with flammable/ explosive materials.
5. Never heat an organic solvent (alcohol, ether, benzene, etc.) in an open vessel over an open flame. These solvents are highly flammable, especially with an open flame - use a hot plate to heat these liquids that should be in an open vessel when this operations perform. See number 7 below.
6. Avoid pointing the mouth of a vessel being heated toward any person, including yourself and the instructor.
7. Never heat reactants in a fully closed system - be sure the system is open to the air to prevent a pressure build-up and explosion.
8. Never add anything (including water) to conc. acid - instead slowly add the acid to the other substance to avoid acid splashing.
9. Hold glass tubes and the thermometers in a towel when pushing them through rubber stoppers.
10. Never pipet anything by mouth - especially toxic or corrosive substances.
11. You should immediately sweep up spill taking place on the balance.
12. Be sure to label all chemical containers correctly.
13. Do not perform any unauthorized experiments.
14. Beware of hot glass tubing - it looks cool long before it can be handled safely.
15. Never throw matches, litmus or any insoluble solids into the sink.
16. Avoid using excessive amounts of reagents - 1 to 3 mL is usually ample for test tube reactions.
17. Do not lay down the stopper of bottle. Impurities may be picked up and contaminate the solution when the stopper is returned.
18. Do not heat thick glassware such as volumetric flasks, graduated cylinder, or bottles; they break easily with heat.
19. Never pour anything back into a reagent stock bottle - take out only as much as you will use.
20. Tie back long hair and refrain from wearing flowing, fluffy clothing - both are fire hazards in the laboratory.
21. Know the location of exits, fire extinguishers, eye washers, first aid kit and other safety devices in the laboratory.
22. De-Ionized water may be obtained through the gray faucet near the first two sink. (Generally, it is good lab technique to do a final rinse with de-ionized water when cleaning glassware
These are by no means the only safety precautions you should take when working in the laboratory, but instead it is a guide as to how you can avoid some of the common hazards. Above all else, use common sense precautions such as cleaning-up after a spill, not picking up red-hot objects, no horseplay in lab, etc.. Following the precautions and rules mentioned above and discussed in the first day of lab, as well as your head so that there is a high degree of safety in the laboratory.
I am aware that there are hazards associated with being in a chemistry laboratory. I have been made aware of the safety equipment available in A-117 and how it is to be used. I have also been made aware of some common hazard such as: broken glass fire, acids, bases, and the poisonous nature of most chemicals. I will always wear my safety glasses during lab. I understand that special precautions for individual experiments will appear in the lab manual in a section entitled "Safety".
(please sign your lab manual below).
Signature: ___________________________________ Date _________________________
Day / Time of Normal Lab Meetings _____/______
Fill in the Blanks
Indicate in the space provided whether each of the following lab safety statements is True (T) or false (F).
1___ It is okay not to wear safety glasses or goggles while working in the laboratory with chemicals.
2___ Before working on an experiment you must know the location of the fire extinguisher, first-aid kit, eye wash station and other safety equipment in the laboratory.
3___ Never eat, drink, or smoke while in the laboratory.
4___ Never taste any chemicals in the laboratory. Consider all chemicals to be hazardous unless instructed otherwise.
5___ Wear shoes at all times while working with chemicals in the laboratory.
6___ If any chemicals contact your skin or eyes, flush immediately with water, and then notify the instructor.
7___ Perform all reactions that involve gases with an unpleasant odor under a fume hood.
8___ Never directly smell a gas or vapor; instead, waft the scent gas toward your nose using a cupped hand.
9___ Never point the open end of a test tube toward yourself or your neighbor when heating a chemical.
10___ Lubricate the rubber stopper hole with glycerol or water before inserting glass (i.e., thermometer) in stopper.
11___ Pour acids into water --not water into acid-- because the heat of solution will cause the acid to splatter.
12___ Do not use alcohol or other organic liquids near an open flame.
13___ It is okay to dispose of all solutions including all organic chemicals down the sink.
14___It is okay to perform any unauthorized experiments.
15___ It is okay to disregard the special safety precautions mentioned in each experiment.
16___ The instructor must be notified immediately in case of an accident, but after the emergency has been addressed.
17___ Read the experiment before each lab including: Objectives, Discussion, Procedure, & Pre-lab Assignment.
18___ If glassware breaks while in use, it is okay to leave it alone, not to clean it up, and not to tell anyone.
19___ Record your observations directly in your data table. Do not record data on loose, unbound, notebook paper.
20___ It is okay to eat snacks or your lunch (dinner) while conducting the experiment in the laboratory.
21___ Never place chemicals directly on the balance pan (without a weighing paper or weighing boat).
22___ Never place a hot or warm object on the balance pan. Allow objects to cool to room temperature so as to avoid weighting errors.
23___ After heating an object, do not immediately place it on the desktop. Allow the object to cool to in order to avoid scoring the desktop.
24___When an experiment calls for water, use distilled water. When cleaning glassware, use tap water & rinse with distilled water.
25 ___ Returning all community lab equipment to its original place, i.e., return ring stand to location under east sinks. Place excess solid chemicals in a waste-crock or other designated waste container. Clean your laboratory station upon completion of the experiment
When this safety quiz is returned to you graded, note which items are incorrect and correct these. Turn back the quiz to your instructor. This quiz is your contract that you will abide by all safety rules of the laboratory. Failure to comply will reduce your grade in this quiz accordingly
Volume 72 Number 12 December 1995 1126
Safety Is No Laughing Matter
Patricia S Hill and Thomas G. Greco
Millersville University P0 Box 1002 Millersville PA 17551
Each fall semester a new group of students, many of whom have little to no previous chemistry laboratory experience, fill the general chemistry rosters at our university. During the first laboratory session in all courses, substantial time is spent demonstrating and teaching proper techniques for the safe handling of chemicals and equipment and for the operation of various safety devices such as eye wash stations, showers, and fire extinguishers. Students also read and sign an extensive safety checklist that is discussed during the first lab session.
In order to reinforce our commitment to developing students who practice "safe chemistry", we begin our fall chemistry seminar series with a presentation on safety in the laboratory Regular attendance at chemistry seminars is encouraged by awarding extra credit points in general, organic, and quantitative analysis courses for attending a certain proportion of seminars during the semester. Students obtain faculty signatures in order to verify attendance. In addition, all paid student laboratory assistants are required to attend the safety seminar. Such a safety presentation might conjure up expectations of a boring rehash of seemingly endless lists of do's and don'ts for students to hear and remember. In order to raise our students' awareness of and interest in safety, we have introduced what we believe to be a novel method of presentation. It attempts to ensure that the students will remember most of the important do's and don'ts of safety.
For the past four years, we have put on a safety skit in conjunction with the showing of the ACS video Starting with Safety. Then we engage beginning students in a contest to identify and list the most safety violations they observe during the skit. The contest winner (student with the most correct observations) receives a molecular model kit provided by our ACS Student Mfiliates organization. Of course, the "actors" for the skit are two faculty members, one of whom is the department safety officer. They portray "typical general chemistry lab partners" who are making up a missed titration experiment lab. At the conclusion of the skit, contest sheets are collected and a group discussion of the observed safety infractions occurs between the audience and the actors. Copies of the skit's script with all safety violations noted with numbers in parentheses and a corresponding table of safe lab practices are distributed also (See table). We present the skit's script with the hopes that you will adapt it to suit the needs of your students and faculty and to enliven an important topic. The skit requires a few simple props that should be readily available in the laboratory It can be performed in almost any sized room as long as there is a bench or table to simulate a laboratory workbench.
• table or demonstration bench
• test tubes with colored water in rack
• metal test tube holder
• Bunsen burner and striker
• buret on stand
• scrupulously cleaned reagent bottles (glass with ground glass stoppers) one labeled ACID but filled with water and one labeled BASE but filled with water
• two Erlenmeyer flasks (one having a broken neck)
• four scrupulously cleaned glass beakers (two containing edible NaCi-unlabeled-and two empty
• clean transfer pipet (25 mL)
• beaker filled with water but labeled ETHER
• 100-mL graduated cylinder on tray (containing several milliters of dish detergent)
• .50 mL of freshly diluted 6% hydrogen peroxide in dark bottle (CAUTION: oxidizing agent)
• Potassium iodide (KI)
• various beakers and flasks with colored water or lemonade
• trash can
• two pairs lab goggles
• lab notebooks
ActorsWoman dressed in good clothes, wearing sandalsScene
Purse with makeup and small mirror (lipstick or mascara)
Bag of carrot or celery sticks in plastic bag
Bag of chips or pretzels
Can of soda
Safety goggles on top of head like hairband
Man dressed in shorts,T-shirt and baseball cap, wearingsandals and carrying a backpack and a pack of cigarettes
Wearing glasses but no safety goggles
A young woman wearing good clothes (1) and sandals (2) is at a cluttered lab bench (3) with a purse and lunch sack (4). A young man, dressed in shorts (5) and wearing sandals (6), enters and greets her. They are lab partners and must make up an experiment they missed (7). She is wearing her safety goggles like a headband (8) on her head and warming (incorrectly, of course) (9) a test tube full of colored liquid over a tall, yellow Bunsen burner flame (10). Next to the Bunsen burner is a reagent bottle labeled "ETHER" (11).
She: Gee, I thought you weren't coming, so I started the experiment.
He: Sorry I'm late but the prof was long-winded. I really need a smoke (12). Can you give me a light?
She lights his cigarette with the Bunsen burner (13). He then plaoes the lighted cigarette next to the bottle labeled "ETHER" (14).She: Oh, hey I brought along some munchies to keep us going this afternoon. Want some? Here, have a carrot stick and some chips (15). She hands him a carrot stick, takes one herself and offers him some chips.He: Thanks, I'm starved. He takes a corrot.She: Yes, one of these is sodium chloride. Humm.
Hey you got any salt?
She looks at two beakers containing white solid chemicols.He: Well, I guess we'd better get started or we'll never get out of here. Do you know what experiment we are supposed to do today? (20)
Lets see which one was it?
They dip their fingers into the beakers ond toste each one (16)
Oh yeah, that's it.
She hands him a can of soda.
Here's a soda to share (17).
While he opens the soda can and pours equal amounts into two clean beakers (18), she proceeds to apply lipstick or mascara (19).
She: Yes, I think it's the one on titration. Did you bring the lab manual? I forgot mine.
He pulls out a lab manual from his backpack and hands it to her She leafs through the book and finds the experiment.He: Here this is it.
Here it is. Acid-base titrations. It says you must first pipet 25 mL of hydrochloric acid into an Erlenmeyer flask. Which one is that? (21)
He picks up a flask with a broken neck (22), then he changes his mind and gets one that is not broken.
She reads more of the lab book.He: Give me something to stir it with.
Why don't you do that while I fill this buret with a solution of sodium hydroxide.
He obtains the acid by mouth pipetting (23) directly from the reagent bottle (24) labeled ACID. He lays the bottle top on the bench (25). She pours out some base and proceeds to fill the buret and spill BASE all over the bench (26). She wipes it up with her hands (27) and then pours the extra BASE back into the reagent bottle (28). Continuing to read directions from the lab manual.
Now it says to dilute the acid with about 30 mL of water and mix it well. He measures out the water andpours it into the acid solution (29).
She hands him the thermometer and he mixes the acid and water with it (30). He then wipes the thermometer on his shirt (31).She: Now we have to add the base gradually to the acid until we see the endpoint. She starts rapidly adding base from the buret (32) but no color change occurs. They continue to add an entire buretfull to the flask.He: Gee, this doesn't seem to be working. There must be something wrong with these chemicals. He opens the reagent bottles and takes a big sniff(33).She: I think that was everything. Oh, oh. Maybe we did forget something. What is an indicator?
Humm. They seem to be ok. Are you sure you read all the directions?
Frantically she leafs through the lab mon vol.
He: Whining. Does that mean we have to start over?
She spies the hydrogen peroxide and KI on the bench.She: Humm. Lets have some fun. I wonder what would happen if we mixed up these chemicals? (34) She pours about 50 mL of 6% H2O2 into a 1OO-mL graduated cylinder containing 2-5 -mL dish detergent.He: Gee, I don't think you should do that.
She: Oh, don't worry so much. They wouldn't leave any-thing dangerous out for students, would they?
She adds a large scoopula of KI to the graduated cylinder They watch wide-eyed as a large column of foam rises and overflows the graduated cylinder.He: Oh, oh! I think we'd better get rid of the evidence (35)and come back another time. They pour everything down the drain (36) and leave without much cleanup effort (37).It has been our experience that combining the video and skit into one presentation is both effective and entertaining. The video introduces fundamental safety concepts, and the skit allows for their immediate application. Students are challenged to be careful observers. Winners of our "spot the safety violations contest" have been able to observe and list all the different poor lab practices during the 10-15 mm-long skit, and most students observe at least 15-20 violations. Most students leave the seminar with a more positive attitude toward safety and their ability to apply it. The more experienced students still find the seminar to be informative and relish the chance to spot infractions by faculty Many junior- and semor-lev~ students have seen the skit three or four times and look forward to getting a laugh from the faculty members' "academy award performances". Overall, we have found this experience to be worthwhile. It should leave a lasting impression on students and result in the responsible practice of lab safety
Safe Laboratory Practices
1. Wear older clothes to lab.
2. Do not wear sandals when working in lab.
3. Keep lab work space uncluttered.
4. Do not bring lunches into lab.
5. Do not wear shotts when working in lab.
6. Do not wear sandals when working in lab.
7. Do not work alone in lab or after hours without permission.
8. Wear safety goggles at all times.
9. Point tubes with liquids being heated away from others orseif
10. Adjust burner flames properly.
11. Do not place flammables near open flames.
12. Smoking in lab is not permitted.
13. Keep hair and loose clothing away from flames.
14. No smoking in lab.
15. No eating in lab.
16. Never taste chemicals.
17. No drinks in lab.
18. Never use lab glassware as food or drink containers.
19. Do not apply makeup in lab.
20. Come to lab well prepared.
21. Familiarize yourself with laboratory equipment.
22. Place broken glassware in the proper waste container.
23. Never pipet liquids by mouth.
24. Do not pipet directly from a reagent bottle.
25. Do not place the tops of reagent bottles on the lab bench.
26. Use care and a funnel when pouring liquids to avoid spills.
27. Do not wipe up chemicals with your bare hands.
28. Never return excess chemicals to the reagent bottle.
29. Always add acid to water.
30. Never use a thermometer as a stirring rod.
31. Do not wipe chemicals onto clothing.
32. Always read and follow directions carefully.
33. Use caution when noting the smell of a chemical; wave the odor toward your nose.
34. Never do unauthorized experiments.
35. Do not try to hide mistakes.
36. Dispose of all waste in the proper location.
37. Clean up your laboratory bench area when finished.