Is the School Laboratory a Frankenstein? JOHN S. SHAW Hercules Powder Company, Wilmington, Delaware
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Y DAUGHTER came home from school one day wrth mflamed eyes and a bad bronchial cough. She explained that her art class had been etching glass, and the "stuff" they used for etching irritated her eyes and lungs. I asked the chemistry teacher a t the school, a man I knew, to investigate. He found the art classes working in a closed room with hydrofluoric acid, with no idea'of the potency of the acid or the proper precautions for using it. He promptly arranged for all art cIasses to meet in his laboratory and work under ventilating hoods until the project was completed. The incident brought to a head for me a long-held belief that too many of our schools and colleges are potential frankensteins, ready to cripple and scar their students through ignorance of chemical safety. Failure to take proper safety precautions has led to accident after accident in student chemical laboratories. Some are small . . like a spark burn from spilling metallic sodium on a desk where water had not been wiped up. Others are large . . . like eyes burned out and flesh eaten away by exploding flasks of hot acid. But very few laboratories in the thousands of schools and colleges throughout the country can report a perfect safety record. In talking to my daughter's chemistry teacher, Herschel Loomis, I found that he, too, had long fretted over the need for a planned safety program for student chemical laboratories. That the incident which provoked us to action occurred in an art class rather than in a chemical laboratory did not alter the need. Rather, it highlighted it. For, fundamentals of chemical safety, once learned, are applicable in the laboratory, the art room, the home, practically every place that houses human activity. Chemical safety is built upon two solid rocks: an understanding of the laws of chemistry and physics that govern the elements and their compounds, and a thorough planning for aU the possibilities that may result from their chemical-physical behavior or misbehavior. Young people just beginning their study of chemistry cannot be expected to have a thorough knowledge of chemical matter. That knowledge comes with years of experience. And yet students cannot afford to learn by hazardous trial-and-error. They need a set of safety rules that explain the behavior of the more active elements and give directions for controlling their activity without creating an accident-situation. They also need to know what to do in case an emergency does arise. A set of safety rules! From our combined class-
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room and industrial experience, Mi. Loomis and I wrote down every chemical hazard we knew and how best to avoid it. We asked the help of chemistry instructors in nearby schools and colleges. And then we submitted the list for further amplification to scientists a t the Hercules Experiment Station who devote their lives to the study of how chemicals react, and why, and how to control those reactions to achieve material benefit. When the list was completed, it automatically broke into two sections-the safety precautions for chemistry students, and the precautions that were the instmctor's responsibility. And thus it was printed, with the student's instructions on one side of a placard for ready reference, and the instructor's information on the other. One placard was used for both sections with the thought that, if students and faculty each know the responsibilities of the other, the two groups working together form a double guard over full enactment of the safety regulations. Safety instructions for students are deliberately kept close to situations they will experience, rather than profound generalities. How to handle equipment, what precautions to take with certain chemicals, a proper .respect for flammable materials-these instructions are applicable from the start of high-school chemistry through the advanced stages of college study and into the industrial or technical laboratory. For example, when glass tubing is heated for bending, many a burned palm might be prevented if a student held a hot tube with his tongs close to but not touching his free hand and tested its heat by blowing across the tube against his hand to see if the tube warms his breath. An amateur testing for ammonia or similar odorous chemicals often draws in a good whii gf an unknown compound. If the tester will waft a httle of the air above the chemical toward his nose with one hand and smell an air-diluted vapor, he may save himself a deep draught of possibly poisonous gas. If the teacher or the members of my daughter's art class had learned in chemistry that "chemical vapors are generally poisonous to breathe" and certain ones should be liberated only under ventilating hoods, they might have thought twice before sticking their noses into hydrofluoric acid vapors without adequate ventilation in the room. They "might" have thought, indeed! One of the most difficultpoints to put across to chemical expertsthe men who determine the course of study for students of chemistry, the men who insert or delete safety information-is that boys and girls in the average student
group are inexperienced, prone to carelessness, and from matches and open flames. The common use of sometimes totally irresponsible. ether should be recognized as fraught with danger beConsider the case of the laboratory class busy pur- cause of the readily flammable nature of this solvent. suing the experiment assigned for the day, except for Yet, even though they sound logical, the number of one boy bent on his own experiment. He was heating times those precautions are not taken is legion. two quarts of villainous-looking brown liquid to which Instructors, too, are sometimes thoughtless. One he added a dash of one chemical and a jigger of another young instructor found a leak in a hydrogen sulfide from time to time. Just,as be got the material to boil- generator being worked very properly under a hood. ing briskly the instructor came up behind him. Instead of fixing the leak under the hood, he rushed 'Wbat is that?" asked the instructor. with the generator across the laboratory to the sink. "I got hold of some toluene," the boy answered The fumes overcame him and he passed out. As he fell, he hit his head on the corner of a desk and lost an eye. proudly. "I'm making trinitrotoluene." Industrial chemical laboratories have found i t adThe instructor wrapped the flask in every available towel and tiptoed to the basement holding the poten- vantageous to stress the importance of eye protectial bomb tight against his chest. He poured the mix- tion and some insist that safety glasses be worn a t aU ture over some blocks of ice, thereby slowing down the times. The industrial company usually pays the enreaction. Questioned later, the student said, yes, he tire cost of eye protection programs. No more tragic knew that TNT was explosive, but he never thought interruptions of careers can occur than sudden loss of about its being dangerous in the laboratory. He eyesight through accident. It would be a splendid simply never thought.. . thing for school laboratories to follow this lead to the What to do in case of emergency is also fundamental. best of their abilities. Water is the primary antidote in the chemical laboraThe question of laboratory ventilation has received tory, whether it be for washing acid-stained hands in considerable attention lately. Ventilating hoods located the laboratory sink, or as a life preservative in a safety over desks to carry out the toxic fumes are no longer shower. Knowledge of first aid is a valuable attribute considered sufficient. Ventilation should be achieved both at the ceiling and the floor of the laboratory. for a student chemist. Safety instructions for teachers and laboratory In one college laboratory, a student doing a bromine directors attempt to solve potential crises before they experiment got so involved in his paper work in the develop. Among the instructor's responsibilities is the laboratory manual that he failed to notice the stopper proper storage of chemicals. Stored chemicals need to on the flask rise slowly from the force of the heating gas be inspected frequently to make sure that they are re- and release heavy brown fumes that curled down the maining stable; for instance, replace any water evapo- bottle, across the desk, and onto the floor. A draft rated from yellow phosphorus or kerosene from metallic blew one of his papers to the floor, and, as the student sodium. The wise instructor will also arrange chemi- bent down to pick up the paper, he got the full effect cals in such a way on the shelf that students will have of the bromine gas in his eyes. For two days be was the least possible opportunity to mistake a container . totally blind, but gradually the effect wore off and his or to get a poor grip on a bottle and drop it. eyes returned to normal. Floor ventilation might All bottles containing chemicals should be plainly have drawn off those fumes and prevented the nearlabeled. Unless materials found in unlabeled bottles tragedy. Explosions and fires are two very real dangers in a can be positively identified, they should be disposed of safely. Violent poisons should be labeled prominently chemical laboratory. An explosion is over almost before it begins. But i t is apt to result in a fire. Therefore, with the word "POISON." The importance of proper equipment for each experi- fireaghting equipment is a prime requisite of any chemiment cannot $ overemphasized. Stoppers and tubes cal laboratory. The old standby, water, is hard to beat must fit exactly. Pipets should be filled using a suction for fightingfires. A connected water hose should be conpump or aspirating tube, never by sucking the pipet venient a t all times to all parts of the room, including with the mouth; a student is apt to draw some toxic storage closets. In addition, every laboratory should or corrosive chemical into his mouth by accident and contain a carbon tetrachloride extinguisher located poison or burn himself badly. All glass tubing should near electrical equipment to put out electrical fires, be firepolished to remove sharp cutting edges: Not and a foam extinguisher for oil fires as well as for other only should equipment be inspected when it is issued, combustibles such as rags, paper, and wood. Carbon dioxide is a good general extinguishing agent but regularly scheduled inspections keep the instructor acquainted with the condition of all equipment during for oil and electrical fires, and for certain types of its use. They also help to achieve good housekeeping. Class A (combustible materials) fires. Despite their Precautions listed on the Hercules safety chart are higher price, carbon dioxide cylinders are much in use in those that would normaUy occur to a laboratory instruc- industrial laboratories because of their wide efficiency. tor-protective clothing, explosion-releasing ovens, A new development in fire extinguishers is a cylinder ventilating hoods over experiments with volatile flam- that releases a water fog to cool and suffocate the fire. mable liquids, safety glass shields when experiments are Though nothing but highly dispersed water, this fog particularly hazardous, flammable materials guarded blanket is a nonconductor safe for practically every
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type of fire. However, for the average student chemical laboratory, a water hose, a carbon tetrachloride extinguisher, and a foam extinguisher should cover every need. Wool blankets should be provided for use in clothing fires. This is especially important in laboratories handling highly flammable liquids. It is most desirable that the blankets be readily accessible a t all times. But having fire-fighting equipment available is not spfficient. Students must be thoroughly trained in its use. If an excited student grabbed the water hose to put out an electrical fire, he might easily be killed by shock, because water readily conducts electricity. An understanding of the chemistry behind the need for more than one type of fire extinguisher will give a student some background for judging what to do when an emergency does arise. Practically every school these days has organized fire &Us or exit studies. But a chemistry instructor should double check to make certain that his students know how to leave the building in case of fire. A laboratory instructor has a grave responsibility for the safety of his students. One science instructor in a private high school wrote: "For the past 12 years I have watched with great concern the actions of my beginning class in chemistry. Would there be among this group one who would suffer irreparable damage to his body, through some needless and preventable accident? How tragic, if, when time is short, I failed to point out some hazard and an accident occurred which would deprive one of our youngsters of an equal chance in life." If only all chemistry instructors felt their responsibility so sincerely! In beginning courses in chemistry, the instructor will do wen to go through each new experiment with his classes before he allows them to try it. In this way he can point out the right way to do the experiment, and underline the wrong way. Too often, laboratory instructors are not thoroughly qualified for supervision by the knowledge and stability that comes with experience. Too often they are only a year or more ahead of the students they supervise. Instructors, too, cause accidents. For example, an instructor in a college freshman chemistry course was demonstrating how to make hydrogen by the reaction of sulfuric acid with zinc. The experiment exploded, and the highly corrosive acid sprayed the first two rows of the class, causing severe burns to a few and lesser burns to many. By all the elemental rules of safety the instructor should have placed a safety screen between the demonstration table and the students. The chemical instructor, then, is the teacher, the supervisor, and the example of safety in his laboratory. In developing safety-consciousness in his classes, he takes his turn a t the potter's wheel shaping the future. For among his students are the chemists and chemical engineers of the next decade, the technicians who will blueprint the progress of industry. On their appreciation of safety will depend fortunes, the lives of men, and the success of great enterprises. For what good is a
man or a plan or a plant which has been blown to bits! The instructor has other shoulders helping him bear his burden of responsibility. In industry today, nearly every company is studying better safety practices and experimenting with more efficient safety equipment. Many affiliated and independent agencies are also working out better safety methods-such groups as the Bureau of Standards, the Bureau of Mines, the Underwriters' Laboratories, the National Fire Protection Association, the American Society for Testing Materials, the American Standards Association, and the National Safety Council. The National Safety Council has taken some interest in the safety problem in student chemical laboratories. It has encouraged writers of chemistry textbooks to weave safe practices into their texts. It has distributed pamphlets, charts, and posters to chemistry teachers in an effort to make them safety-conscious. The Hercules chart of Safety Instructions in Chemical Laboratories is one of the instruments available to the Council and to anyone else interested in safety. If you would like a copy of the chart to hang in your laboratory, address your request to Hercules Powder Company, Wilmington 99, Delaware. But there is still lots of work in chemical safety education to be done. The Hercules chart does not list all the information needed for safe conduct through a chemical world. It merely seeks to arouse interest in safety, and help in the promotion of safety among the youth of our nation. Through the more complete safety education of the chemistry students of today, we a t Hercules hope to acquire responsible technicians to man our plants and the rest of the nation's industry tomorrow.
The safety education of your students is as much your responsibility as their chemical education. CHEMICAL OPERATIONS
1. Before every new experiment, explain the possible chemical hazards and tell how they can be avoided. 2. Examine all apparatus for defects before it is issued. Inspect it regularly during use. 3. Provide aspirating bulbs, suction pumps, or mbber tubing connected to a water aspirator for filling pipets and starting siphons. Never allow students to use mouth pipets. 4. Provide students with goggles or face shields, rubber gloves, and aprons when handling acids, alkalies, or other corrosive materials. 5 . Keep matches, open flames, and electric hot plates well away from all work with flammable solvents, and preferablyin another room when such materials as ether, acetylene, benzol, acetone, alcohol, hydrogen, or carbon bisulfide are used. 6. Distill or hest all volatile flammable liauids under a ventilating hood, uringa pyrex or other heat-re;i*ting glas, with a safery-ghcs rhirld protecting the operator. Place under tllc flask a pan of su6ctrnt capacity to hold the volume of liquid in case of breakage. 7. For drying explosive or highly flammable material, use ovens equipped with latches that spring open under low pressures. Dry the materials containing volatile flammable liquids in steam ovens under a hood. Never use open flames or electric hot plates unless all electrical equipment is explosion proof.
PIOHTINO PIRES 8. Keep all fire-fighting equipment, such as hand extinguishers and connected water hose in good condition. Inspect them regularly. Drill students on their location and proper use. 9. Provide wool blankets for extinguishing clothing fires and forsmotheringsmall~es,especiallyin laboratories handlinghighly flammableliquids. Treattheblankets for moths and keep them readily available. STORAGE 011 CHEMICALS 10. Store all chemicals so that their labels are prominently displayed. 11. Keep poisons in bottles marked with skull and crossbones and the word POISON. Store them apart from ordinary r b agents. 12. Unless materials found in unlabeled bottles can be positively identified, dispose of them separately and carefully. 13. When storing chemicals on shelves, provide ample space between bottles so that students can grasp the bottles firmly. Spacing can be maintained by wooden strips fastened on shelves. 14. Place heavy bottles as near the floor as possible and brace them well. 15. Some chemicals require particular care in storage. For example, store metallic sodium a i d metallic potassium in kerosene in glass battles sitting in metal cans, because they react violently with water. Keep them away from water drips. Inspect them frequently t o make certain that the kerosene has not leaked awl". - ~~, . 16. Store yellow phu~phoruiby submerging in wntcr in glass bottles sitting in metalcans Inspect frequently for water leakagc. 17. Do not store metallic sodium and metallic pcltas4um near yellow phosphorus. If the sodium or potassium were accidentally returned to a container of phosphorus under water, there would be "fireworks." Remember, these rules are not all-inclusive. They point out only a few of the common laboratory hazards for chemistry instructors to recognize and guard against. To anticipate a n accident, and to prevent i t before i t happens is safety. STUI)I
