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1. Responsibility for Accident Prevention in the Chemical laboratory. Edited by N O R M A N V. STEERE,. School of Public Health,. University of Minnes...
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in the Chemical laboratory Edited by N O R M A N V. STEERE, School of Public Health, University of Minnesota, Minneapolis, Minn., 55455

1. Responsibility for Accident Prevention If you are interested in preventing laboratory accidents, your actions will drpend largely on whether you are t h r student ur investigator, the instructor, or tll? ntiminist~mtor. The student or investigator has an individual respmsibility to avoid nrcidents, the instructor h:is :l supervisory responsibility, and the adminietr:~tor has a n institutiond responsibility. 1-ndersbanding and nrrepting tlres? mponsibilit,ies is necessary for r R ~ r t i v f * p r ~ v ~ n t i oofn lnboratury seridmts. I n d i v i d u a l Responsibility With the trend toward stnrting independent research projects a t the u n d ~ r graduate and high school levels, there must h r an inrreasine screotanee of individual rrspunsihility for knowledge of chemical hazarcls and safe laboratory practice,%. There is nothing unscientific or organisntionnlly cmforrnistic about learning and prartiring enough safety t o stay alive and in one piece while doing research. There nrr already Lou many chemists who disregard the potential hazards of m:ttrri:ils nnd equipment they are working with. A st,udent who is planning nn investigatiun slmuld: Find out the health and snfetg hnsnrds ui the ehemirals t o be used and produced and the hazards of the reactions whirh may

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Ilesign the experimental setup and pmredores t o avoid or limit unplanned orrorrences. and Investigate and record u n p l a n n ~ devents which ornlr. Such a seemingly sinrple proredore ma>be diffirnlt t o practice routinely but mnking the procedure routine will protrrt, th? student in college and in f u t w r work.

-Editor's Note The nrrompanying article iaaogunles 3 Dew Chem Ed Feature, n rontinuing series "Safety in the Chemical 1,alxmt,ury." The editor for the series and anthor of this ~ontributionis eminently qualified t,o discuss saiety mntters. H P is n member of the faculty and S n f ~ t y Engineer in the Srhoal of Publir Health, University of Minnesota, l l i n neapdis. Plans for the series include highly informative discwsions ui availnble equipment as well as snrressfol sofety programs. Accident. rase histories will be included. The editors will he grateful and encouraged to rer r i w the participation of r~ndrrs in future columns.

Find Out the Hazards All of t h e rhe~niealar h i r h n n y bp involved in a reaction or a ~ r i of ~ srcnctions must. be considered in onlnr to assess :ill the hazards and t,o pmvidr fir rontrd of arcident,~. I n addition to the reacting chemicals and their impurities, cunsiderstian must be eivm to t,lrp lmmrrls 01 chemicals used fur: 1)issolving-ether, nlnhol, hename,mrbon tetrarhlovide, etc. Heating-oil in haths, furl gas in hurnem. Cooling-liquid nitrogm, nret,one-dry ice, etc. Cleaning-aretone, rhmmir acid, etr. Drying-concentrated sulfurir, magnesium perchlorate, d c .

The hw.rds to he a s y e w 4 are t,hose related t o hedth, Hnmmshility, and renrtivity of the rlremirnls, and those related t o type and rate of reaction, including n ~ e d sfor ventilation, pressure relief, r m ing, inerting, or other sperinl cuntmh. Health hazards of rhemicals sl~ooldbe ant,ieipated, w e n if a sonrrh of the literature does not e i k sperifir warnings. The toxicologir patent,ial of many, many chemicals has not yet been investigated-and esposing students and investigatrm to untested rhe-rnirnls is not an approved method of tcstine. Surh nn experiment is poorl,v designed, lneks controls and is difficult to reproduce. There is no good reason why t,here should 1,e injuries irnm ehemirnls whose health hnartrds have been evnlnst,ed and reported in the literntnre. Sourres of information on h d t h haanrds include tlir AIHA Hygienic Guides and the Juurnnl of AIHA, Chemical Safety Dntn Sheets uf the Manuf,zrt,urinp Clwnists' Association, Inc., Threshold Limit Values of the ACGIH. and several of the references cited in the general bihliugrsphy nppended. Partirulnr attention is drawn t o Smyth's excellent article, which describes nine categories of objectionable efieets and lists and summsrizes the supporting data for the most important inhalation eReet,s of 238 rhemicnls. Srnyth also lists important hnnards other than from inhalation, gives the nnt,ure of the interpretive dat,a, and emphasizes th? limitations of reliance on odor for warning of over-esposure. Stokingerk editorial, commenting on n case report uf laborators fst,alities from unexoectedlr hazardous chemicals, rriticines as all too common the unronscious disregard of chemists for the potmt,isl harm of the produets of their trade and srt. Stokinger suggests that, i t is time in the early chemist,r,v courses to instill

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proper regard f w the torir potential of rhernicals, and t,ime t o require integrated instruction on t,he hazards associated n i t h the prepamtion and handling of com~""'"d~. H:~snrdrof extreme renrt,ivity of chomirals e m be predicted in oumy eases by rnlrulation of the heat oi drcompositivn nnd the oxygen balance as described by lomlinson and Audrieth. Infr~rmntion

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on some incompatible chemicals and some hazardous chen~icalsare described in texts listed in the bibliography and in RIC.4 Chemical Safety 1):lta Sheets. Chemicals %.hirh will lmrn may be a. problem but particular attention should be given tu flammable liquids and gases, because of t,he likelila,ud of explosion or fire if the vapors or gases spread t o sources of ignition. Adequate provisions for control of vapors and gases and sources of ignition depend upon a. inll and realistir apprrtissl of the fire lmssrds of the chemicals. Also t,o be evah~atedare the hazards of unguarded belts on pumps, ungrounded eleetriral equipment, tripping hazards, in:rdequate lighting, high shelves, and otlwr nun-chrmiral injury haaanis.

Design of Setup and Practices Controls that should be provided for flnmnlnble liquids, gases, and solids include firo-protected storage, vent,ilatiun to prevent nrcurnuletion of explosive mixtures, and control of ignition sources. Measures to cuntrol ignition are grounding of transfer between containers t o prevent static elertririty, inerting procedures, and use oi explosion-proof equipment designed t o prevent propagation of Harne. Ventilation msy be provided by adequately operat,ing chemiral fume hoods or by special local ventilation. Fire-prutrcted storage includes fire-resistant storage rooms or whinets, metal safety can3 npproved h y Underxwitem Laboratories, Inc. or Fsctory h l u t u ~ l I,xborntory, or insulated containers fur glass bottles. Reducing t,he quantities of rhemicnls used and stored in the lahr,ratory, particulm~lyfl:unrnnble liquids, is advised a s a meam of ininimizing problems whirh ronld result from fire or explosion. Pntrctiog rontsiners of fl:~mmnble, irritating, rorn,sive, or toxic liquids i~mmbruakage and spills is prudent practire-to reduce the likdilwod :md extent of fire and in,jury. Health hnaards mny require special ventilation, enrlosures for handling, and protective clothing and equipment. Unusual ltenlth hazards may require preventive imnmnisntions or ilnmedinte nvailnbility of s p e d antidotes. Shielding, inerting, and other special prrcnutians may be needed for unusunlly

Volume 41, Number 1 , January 7 964

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reactive chemicals, depending on the kind and degree of hmards. Reaction control requires instrumentation to tell in detail what is going on, and reliahle and fail-safe instrumentation to maintain control. If a thermostat fails, d l the reaction cool rather than continuo heating? Is the thernmstat backed up by a second thermostat or limiting device'? Accident prevention also requires control measures based on consideration of the results of individual and oombined malfunctions of each item in a reaction system. Van Atta states that the best passible n a y to cope with undesirable events resulting from malfunctions or unexpected reactions is to insist t h a t chemists and chemical engineers consider the possible alternatives a t an early point in the design process. As reaction processes increase in complexity, and the cost of error rises, it hecomes more and more important to establish operating procedures which account for and avoid unexpected or uncontrolled reactions. A recorded experimental procedure will be of value in pre-

cidents is the responsibilit,y of the person teaching or supervising. I t is generally accepted that anyone x-ho directs the activities of obhers, as teacher or supervisor, has a responsibility to prevent accidents in such activities. The supervisory responsibilit,y far accident prevention i~ frequently enunciated in industry, and has been enunciated in several universities. One academic safety policy which has been formally adopted reads as follows: "It is the desireof t,ho Board of Trustees of Michigan Stat,e University t o conserve the human resources of the University by prevention of accident8 to staff, students, and visitors which may cause property damage, injury or loss of life. Humanitarian motives impel the enuneiat,ion of the University policy on accident prevention. "It is the policy of Michigan State Uni-

versity to prevent accidents in r o r k , class and other activities whieh the University supervises, is responsible for, or sponsors. Each person, regardless of official or unoflicial status, who assumes or is assigned responsibility far the work or activities of others is administratively responsible for their safety during such u w k or artivitics. Investigation of accidents to staR and students during work, class, or sponsored activities is the msponsibility of the person whose job it is to supervise the person injured. "It is the intention of the University that t h e n shall he compliance with safe oractice standards which are a matter nf professional knowledge, a n d with official codes and regulations. "Each department is responsible far the establishment and preservation of safe conditions and safe practices within the area of jurisdiction of the department." ~~~~

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there should he estathshed n b practiced emergency procedurerr. Emergency procedures may be needed for evacuation, rescue, and control if a. reaction geta completely out of control, if a. bottle of d v m t or arid breaks, or if a cylinder leaks corrosive gas. Preparation for emergency procedures can be vital for swing lives and invaluable for limiting damage within a laboratory and preventing spread of fire or contamination through the building. Investigate and Record Unplanned Occurrences

Any unplanned occurrence, or accident, which results from Inhorntory experiments or equipment should be investigated and recorded: for revision of experimental procedures; for modification or redesign of equipment; for safe design of scaled up processes and reaction vessels; and for evaluation of emergency procedures. Smyth suggesta that simple self-interest should dictate making public what is learned for the benefit of fellow specialists, while Van Atta is bothered that Iahohoratory incidents do not often enough result in learning that is used to prevent industrial incidents. Reports of laboratory aceidenta, even without proposed remedie., can be useful for identifying hazards and supporting corrections; other colleges and univemities are interested and can benefit from exchange of information. Reports are solicited for uae in these columns; identities will be protected.

Supervisory Responsibility Above and beyond individual responsibility for prevention of laboratory acVolume 41, Number I , January 1964

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At th? University of Minnesuts, the President sent a letter t o all academic and supervisory staff which reads ns f0lhw~: "To serve as a guide in our continued efforts t o reduce accidental injuries, the following statement of University safety policy is set forth by the All-Tlnivenity Committee on Industrial Safety: "It shall be the policy of the University that student, visitor, and staff snfety be of first consideration in every enmpus activity. I t shall be our aim t o build ' every structure, plan every activity, and perform evenr task so t h a t the possibility of accidental injury is reduced to a minimum. Further, it will be the purpose of the University and its faculty to develop a positive attitude toward ssfety within the student body that will remain with these individuals into their professional and community lives. "To make this policy effective, it is requested t h s t the Ilesns and Department Hrnds be continuously cognizant of the safety needs of their pelgannel and initiate nerossnry preventive measures t o rontrul safety hazards associated with activities under their direction. I t is essential t h a t all supervisors, both academir and civil service, understand and accept this responsibility for the safety of all persons coming into their areas and for the safety of all personnel under their direction. I t is further requested that ssfety be incorporated as a n integral part of all courses in which there is a hazard of accidental injury in t,he classroom, laboratmy, or shop. "In t,he imnlementation of this snfetv -~~ < policy, i t is urged thst the sdvieeand counsel of the All-Vniversity Safety Committee. . . and the services of the safety engineer and other professional staff of our Trniversity Health Service be used st every upportunit,y . " ~

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Institutional Responsibility I t should be obvious that adoption and enunciation of a safety policy will only be effective if t h e institution, or administrative subdivision, demonstrates a willingness t o support the policy by furnishing the facilities and equipment necessary t o provide a safe working environment. If such an environment cannot be provided immediately, the institution can demonstrate its support by s n organized prcgram t o make continuing improvements. A department or an instit,ution has two or three bases on which to justify expenditures for safe laboratory equipment and facilities. The first may be the most apparent-to prevent injuries to students, damage t o equipment and damage t o huilding facilities. The second basis is to carry out sponsored research with a minimum risk of interruption or loss. The third and perhaps most important reason is that z safe laboratory is in itself a fundamental part of the educational erperirnrr for &ieh the institution exists. (Cmtinzred on page A 3 5 )

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Elements of o Safe loborotory Environment A brief and partial list of some elements of x safe laboratory environment would include: Adequately designed and maintained ventilation systems, including chemical fume hoods with sash snd adequate face velority. Fire protection for chemicals. Fire extinguishers adequate and appropriate for the hazards. Eyewash fountains and safety showers. Self-contained air masks near the lahoratory for rescue purposes. Two means of egress as far apart as possible. Safe methods of disposal of hazardous waste chemicals and materials. Adequate storage and bench spare for the needs of the work. Means of preventing spread of fire from on? floor to another. Forms for Recording Accident lnvestigotions The sad fact is that injuries do occur in laboratories. An effort should be made to determine n h a t injuries are occurring and to find out what the eauses are so that similar accidents can be prevented. Minor injuries can he an indicator of hazards which can cause more serious injuries. As an aid to assessing laboratory aecidents, some form is needed as a guide for recording the facts and causes. We recommend a form which asks for basic causes and provides a list to choose from. If the person injured and t,he person investigating the accident both give thought t o the selection of appropriate causes, the experience generally will help both learn what they can do to prevent similar accidents. The best suggestions for preventing an accident may come from the injured person, and if basic causes are agreed upon, corrective actions will usually he apparent. One fairly simple form for accident recording. using a basic cause analysis system is that in use a t Michigan State IJniversity, East Lansing, Michigan. Interested readers can obtain copies from the Office of Safety Services a t MSl1 or from the author. loborotory Safety Experience Two summaries of student areidents at one university are shown helow to give an idea of some sources of labomtory injuries, and one means of classifying such injuries. Of 225 injuries reported by students in all of the university laboratories, the first table summarizes 95 injuries in the chemistry department and the second summarizes 65 potentially aerious injuries in all departments. Such summaries are used within the university to provide each department with a record of the accident experience in their laboratories. Preventive efforts within the chemistry department may be responsible for the 23% decrease of student injuries in t,hat department from the previous year. (Conlinued on page A36) Volume 41, Number 1 , Jonuory 1964

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Organization far Safety The best organization for safety is one that works. There are situations where Student Injuries in Department of Chemistry Laboratories Source

Head

Broken glassware Chemied spills Equipment (:lass tubing, etc. Uneontrollid reaction

Part of Body Injured Hand Body Leg

Arm

Foot

Int,ernal

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0 3 0

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*Three injuries resulted from chemicals entering the eye. The use of eye protection as required prevented nine eye injuries. Potentially Serious Student Injuries Occurring In University Laboratories Source of Injury

Head

Arm

Part of Body Injured Hand Body Lee Foot Internal

Broken glass Chemiral spills Electricity .... Falls

Foreign bodies Hot liquids hlech. equipment l'ipetting Syringes Ilneoutrolled reactions Vapors or gases

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Note: Not included as potentially serious injuries were 42 aecidente involving broken glass tubing, usually while inserting in x stopper, 23 accidents involving hraken glassware and 18 involving sllsrp hand tools. Almost all resulting injuries were minor cuts to the hand. 'Over 50% of these injuries could have been prevented if safety eye protection had heen worn.

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Journal of Chemical Education

safety committees can help, hut we agree with DeReamer in Modern Safety Pmclice8 when he refers to committees as a "sacred idol" of the safety movement, and auggeats an orderly program for diebanding them. Before you advocate such a step you should, of course, examine critically the performance of your d e partment'a safety committee and what needs to be done. Sperial committees, set up to perform a specific task or group of tasks, have had same outstanding successea-perhaps because the best people were willing to work on a short-term project, whereas they would not have served or been effective if appointed to a cammi6 tee for "life or goad behavior." The only certainty a t this point is that there are problems, and a variety of effective approaches is needed.

Bibliography BAHME,CHARLES W., "Fire Protection for Chemicals," 2nd ed., NFPA, Boston, 1961. Runxs: CRAIG,J. CHEM.EDUC., 33, 508 (1956). CRAMBEELAIN, MARKM., hrational Safety Council T~ansactions(Chem. & Fertilizer Ind.), 5 , 4 0 (1962). CHAMBERLAIN, MARK M., A N D JABS,GERHARDT,A., J. CHEM. EDUC., 37, 446, 51 1, 583 (1960). COOK, WILLIAMB., A N D PERKINS,A h FRED, J., J. CHEM.EDUC., 31, 95 (1954). (Cmtinued on page A41)

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IIEREAMER;RUSSELL, "Modern Safety Practices." John Wiley B Sons, Ine.. New York, 1958. Dow Chemical Co., Industrial Research, 5,

KO.6, 14 (1963). Factory Mutual Engineering Tlivisian, "Handbook of Industrial Loss Prevention," McGrawHill Book Co., Neu. York, 1959. FAIRHAI.L, LAWRENCET., "Industrid Tuxieologv," The Williams and Wilkins Co., Baltimore, 1957. FAW~ETI', H. H., J. CHEM. Eouc., 27, 108 (1949).

GUELICH,JOSEPH T., "Chemid Snfet). Supervision," Reinhold Publishinp Co., New Ynrk, 1956. "Handbouk of Organic Industrial Solvents," 2nd ed., National Assoriation of Mutual C;tsuslty Companies. Chicago, 1961.

"Hazardous Chemicals I h t a , " Xntional Fire Protection Association, Boston, 1962.

LEWTON, LUCYO., J. CHEM.EDUC.,28,491 (19511.

Los Angeles Fire Dept., "Dangerous Chemicals Code," Parker and Co.. Los Angeles, 1951. ~IACOMBER, ROBERTD., J. CHEM.EDUC.. 38,367 (1961).

Manufacturing Chemists' Association, Ine., "Guide for Safety in the Chemical Laboralory," I). Van Nost,rand Co., In