Safety in chemical laboratories. An industrial ... - ACS Publications

protects himself, his associates, and industrial property. If he cannot do these things, his employers cannot afford the risk of retaining his service...
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SAFETY in CHEMICAL LABORATORIES An Industrial Viewpoint

FREDERIC WALKER E. I. du Pont de Nemours & Co., Inc., The R. & H. Chemicals Department, Niagara Falls, New York

Industry demands that its chemists be safe workers. do these things, his employers cannot afford the risk An industrial chemist must be constantly on guard of retaining his services. The following extract from the R. & H. Safety News against the hazards involved in his work; he must know safety rules, and he must make use of equipment which which is published by the R. & H. Chemicals Dept. protects himself, his associates, and industrial property. of E. I. du Pant de Nemours and Co., Inc., for its If he cannot do these things, his employers cannot afford employees illustrates the value of safety in industry the risk of retaining his services. The present article and shows the industrial attitude on the subject. describes the attitude of a n industrial concern toward the It concerns the Pacific R. & H. Chemical Corporation question of safety and tells of some of the methods em- which manufactures Hydro-Cy (hydrocyanic acid) ployed in industry to increase the safety of the chemical for use in combating the pest known as "scale" which attacks citrus trees. worker. During the period of its existence (14 years), this company has had no fatalities among its employees as a result of exposure to hydrocyanic acid. This record is not accidental, hut is a result of the appreciation of the problems involved and a definite determination an the part of each member of the organization to avoid accidents. The personnel has been carefully selected and trained in safe operating conditions. Safe methods of handling the materials and equipment have been worked out. Every employee is required to learn the methods applying to his work and to follow them implicitly. Every employee knows that carelessness on the part of any one of the group may result in serious consequences, not only to the careless individual but to others as well. Accordingly the careless workman is not tolerated by his fellows.

N AN article recently published in THIS JOURNAL,^ P. L. Turrill discussed the legal aspects of accidents occurring in the laboratories of schools and colleges and emphasized the importance of accident prevention. The methods that might he employed to prevent such accidents were described. Certain aspects of safety in the industrial laboratory have also been discussed by B u x b a ~ m . ~The object of the present paper is to set forth the attitude of an industrial concern toward the question of safety and to describe What is said here with respect to the manufacture of some of the methods employed in industry to increase the safety of the chemical worker, with especial refer- hydrocyanic acid applies with equal force to the whole ence to safety apparatus and its r61e in the lahora- field of industrial research work. In fact, the importance of safety must be stressed with even greater tory. The question of accident prevention in chemical urgency in fields in which the chemist has to deal with laboratories is an extremely important one for industrial chemicals that appear to be less hazardous. The concerns. It is of importance not only for the personal average chemist does not need repeated warnings to well-being of the individual employee and his associates, work carefully with hydrocyanic acid, mercury fulmihut also because accidents are responsible for large nate, or nitrogen chloride. However, because they are capital losses. Industry has learned the lesson of encountered more frequently in the average laboratory, safety a t the price of bitter experience and demands such chemicals as benzene, methanol, sulfuric acid, todav that its chemists be safe workers. An industrial and even boiling water become insidious sources of chemist must, of course, have a thorough knowledge danger. The following is a brief outline of the various methods of his science but this is not all. He must he constantly aware of the hazards involved in his work and know that are employed for the prevention of accidents in by what means they may be reduced to a minimum industrial laboratories. He must know safety rules and follow them. He must SAFE LABORATORY CONSTRUCTION make use of equipment which protects himself, his associates, and industrial property, and if accidents 1, the first place the laboratory be made safe do take place, he must be to take the Proper for the chemist. This is done by making the question steps to moderate their consequences. If he cannot safetyplay a part in the plans of the architect when the laboratory is built so that fire hazards will be low, 1 T-LL, J. CHEM. E ~ u c .10,552-5 , (Sept., 1933). ventilation good, etc. 1 B u x e ~ mQid., , 11,73-6 (Feb., 1934).

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SAFETY APPARATUS

The laboratory is well equipped with safety apparatus. The nature of this apparatus, which consists of anything from a fire extinguisher to a rubber glove, will be discussed later in greater detail.

is impressed upon all concerned since minor injuries often develop into major ones if n o t a d e q u a t e l y treated.

SAFETY RULES

Rules of the sort described by Tumll in the paper previously referred to are drawn up. The chemists are expected to be thoroughly acquainted with these rules and to follow them implicitly. The figure demonTARR I O WAY ~

1. Make sure that the bore of the stopper is of the proper size for the glass tubing t o be used. 2. Fire-polish the end of the glass tubing. 3. Use glycerin or soap and water on the glass tubing as an aid in inserting it into the stopper. 4. GrasD the rubber s t o u ~ e rbetween the thumb and index finger in such a manner that i& glass tubinp will not come in contact with the hand when it passes through the stopper. 5. Grasp the tubing with the other hand as near the end to he inserted as is convenient. 6. Insert the fire-polished end of the glass tubing into the bored hole of the stopper by gently twisting the tubing or the stopper as force is exerted with both hands. THEWRONG WAY 1. Do not insert glass tubing with jagged and rough ends. 2. Do not attempt to force glass tubing into a bored hole in the rubber stopper considerably smaller in diameter than the outside diameter of the glass tubing. 3. Do not grasp thc rubber stopper in such a manner that the end of the glass tubing will strike the hand holding the rubber stopper, as the end of the glass tubing passes through this stopper. 4. D o not hold the glass tubing a considerable distance from the end to be inserted. This puts a lateral strain on the glass, which will cause it to break easily.

ILLUSTRATED SAFETYRULES Such pictures hung in the laboratory are more effective than rules without illustrations.

strates a pictorial method by which some of these rules may be illustrated. Such illustrations are hung in the laboratories where they may be readily observed. SAFETY LITERATURE AND POSTERS

Company publications such as the one from which we quoted are published a t re~ularintervals to keep the ~mployeessafety-minded. -posters placed on the bulletin boards and hung in the laboratories contribute to the same purpose. SAFETY CAMPAIGNS

Safety campaigns are conducted annually in which the importance of establishing high records of safety is impressed upon all. FIRST AID

A first-aid department is maintained to give prompt treatment to all persons in case of accidents. The importance of reporting for treatment of minor injuries

STUDY OF ACCIDENTS

A report is prepared for every accident describing the accident and t h e methods, if any, by which it might have been prevented. If the accident was due DAMACED GOGGLES to carelessness' the Each pair of goggles probably matter is taken up represents the saving of one or both with the individual of a man's eyes. responsible. Every accident has a valuable lesson to teach and in some cases the injured person is called upon to address his fellow workers and tell them the details of the accident after he has recovered fromits effects.

...... We shall now consider the nature and use of safety apparatus in somewhat greater detail. Its function is to afford the chemist a certain degree of protection from accidents which cannot be altogether controlled and to prevent accidents of a minor sort from developing into catastrophes. Laboratory glassware occasionally breaks when in use. Reactions sometimes get out of control and become violent even in the course of routine preparations. Such happenings may be harmless but they occasionally lead to serious accidents. The writer knows of one case in which a university student was burned to death when a glass container in which he was heating an inflammable solvent cracked and t h e ignited fluid saturated his clothing. His life might have been saved by the proper use of safety a p p a r a t u s . Of course this apparatus will not prevent all laboratory accidents from having serious consequences. Chemicals may detonate with such violence that all screens are useless to protect us from their vioThe housed apparatus consists of lence. Safety appaa sulfuric acid bath with a mechaniratus may even lead cal agitator.

a man to take unwarranted chances in the belief that he is c o m p l e t e l y protected. But the possibility of minimizing the effects of accidents by well-considered safety precautions is none the less worthy of serious consideration. The following are some of the more important types of SAFETYSCREEN s a f e t y equipment An 18' by 24" frame constructed of angle iron containing polished that may be used in wire glass. the laboratory. The more eeneral rules for their use based on industrial practice are set forth. Some of the items, e. g., goggles, fire extinguishers, etc., are present in all laboratories. Other items may be less well known. Apparatus for protection in the handling of exceptionally dangerous chemicals is not described. Such apparatus is designed especially for the work in hand and is not of general interest.

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types available depend on the particular types of fire hazards to be expected and persons in the laboratory should know the value and limitations of each type and the kind of valve employed on each extinguisher. Use of the wrong sort of fire extinguisher for a chemical fire may turn a small one into a large one and can even cause an explosion. FIRE BLANKETS

One or more wool or asbestos fire blankets should be provided in every laboratory and must be conveniently located. It is a good practice to have a woolen blanket suspended from a rack in such a way that a person whose clothing has caught fire can catch hold of one edge and by merely turning his body around wrap the blanket about him. A readily accessible shower is also excellent for putting out flaming clothing. The asbestos blanket is often useful in putting out small fires since it can be thrown over the whole fire. SHOWERS

A shower should be provided in the laboratory for protection in case someone is spattered with acid or other caustic chemicals. Preferably such a shower should be operated mechanically so that it is turned on easily when the person needing it steps on the shower platform. The shower should be tested periodically.

GOGGLES

Goggles for use in the chemical laboratory should possess heavy glass eyepieces and be of a constructiou that offers protection from the side. These goggles should be fitted to the individual. They should be worn when opening cylinders containing gases under pressure, when cutting sodium, using grinding apparatus, in all cases where there is danger of splashing dangerous chemicals, etc. GLOVES

Canvas gloves should be worn whenever the chemist is cleaning up broken glassware. They should also be worn when handling "dry ice." Rubber gloves should be used when there is danger of the hands coming in contact with acids, aniline, or other caustic or poisonous chemicals. Asbestos gloves are sometimes useful when hot apparatus, etc., must be handled. GAS MASKS

All-service gas masks must be placed so that they are instantly available in case dangerous gases are liberated in the laboratory and should also be a part of the regular fire-fighting equipment. They must he kept away from hazards but near enough for convenient use. FIRE EXTINGUISHERS

Fire extinguishers should be kept in hallways or near doors away from the principal fire hazards. Carbon tetrachloride extinguishers, Foamite extinguishers, carbon dioxide extinguishers, sand, and soda ash are valuable aids in putting out laboratory fires. The

DRAIN TRAYS

Drain trays are rectangular iron pans made of sheet metal, e. g., galvanized iron. A generally useful size is a 15" square tray with walls that are 4" to 5" high. These pans should be capable of holding liquids. When glass flasks or beakers are heated over gas burners, either alone or as part of a general set-up, the supportinz riup stand- a n d the burners should be set in these pans. When mercury is poured into a flask, tube, bottle, or other apparatus, the operation should be performed over one of these t r a p . Appar a t u s containing large amounts of mercury should have a plain iron t r a y under it. When it is necessary to keep iuflammable liquids in flasks or glass bottles DEsrcc~~oR HousrNc on the work bench, Vacuum desiccators sometimes the bottles or flasks fail and flying glass is hurled in all directions. The metal case shown should always be set hem is designed to sfford some proi n a d r a i n t r a y . tection to workers in case of such an There is less chance accident. The metal top is placed

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of the containers be-

over the desiccator when it is evacuated.

ing broken in such a tray, and if they are broken, the dangers inherent in such a happening are considerably reduced. Lead-lined trays should be used to hold the bottles of concentrated acids. Of course, it is understood that large quantities of inflammable fluids should not be stored in glass and should never be allowed on work benches on which burners, hot plates, etc., are in use. A modified drain tray which empties its contents into the drain was recently described by W i l ~ o n . ~ Such an arrangement is useful when dealing with noninflammable fluids with the exception of mercury, and when it is not desired to save the material spilled. SAFETY SCREENS

Safety screens are used to afford some protection to the chemist in case of accidents such as minor explosions, lire, or breakage of apparatus. They may be made of some form of heavy or non-shatterable glass, laminated glass, I/," polished wire glass, etc. The glass is set in a self-supporting iron frame. Screens should be placed in front of or around the apparatus that is being used. The size of screen depends, of course, upon the requirements of the particular apparatus. A generally useful size that can be kept on hand in the laboratory is a screen 24" high and 18" wide. The frame may be made from angle iron, 1" by 1". The supporting feet of the frame should extend 4"on each side. Protective devices consisting of a combined safety screen and drain tray are often useful. In the illustration such an arrangement prepared for housing a melting-point apparatus will be seen. It is advisable to place a safetyscreen in front of all vacuum distillations or any evacuated flask and in front of any apparatus in which there is danger of fire, explosion, or splash (e. g., the splash that would result if a flask containing a hot or caustic fluid broke). Safety screens are not guaranteed to protect the operator from all explosions, and are probably not sufficient protection from a real detonation. They are designed to afiord protection from unexpected happenings which would be dangerous to the man directly 8W ~ O N I d,.Eng. Chem., 25,1216 (1933).

WERE SCREENTO Pnorecr LABORATORY W o n r t ~ n s AT OpPOSITE BENCHES This screen will stop most of the flying metal and glass in a laboratory explosion.

in front of the apparatus but would not constitute a serious hazard to other persons in thevicinity. A metal screen surrounding the sides and back of an apparatus used in conjunction with a glass screen is often useful. OTHER SAFETY APPARATUS

In addition to the safety apparatus which has been described, many other pieces of safety equipment have been found valuable in the chemical labbratory. Some of these are (1) metal non-spillable containers for the transportation of bottles of corrosive liquids, (2) chains for the support of gas cylinders when they are in use a t the work bench, (3) rubber bulbs for filling pipets with poisonous and corrosive liquids, (4) separate, covered metal receptacles for broken glass and combustible refuse, and ( 5 ) metal flasks for distilling inflammable liquids.

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In closing, the writer wishes to express his thanks to Mr. J. W. Dunning, Service Section Supervisor, and other members of the R. & H. Chemicals Department, for their helpful cooperation in preparing this paper.