mfety in the chemiccrl lcrborcrtory
edited by MALCOLM M. RENFREW University of ldaho Moscow. Idaho 83843
Safety in the First-Year Chemistry Laboratory Malcolm M. Renfrew University of ldaho, Moscow. ID 83843 I did not know that it was an incinient horror story when I was takmg part in it, but as a participant I recewed some tardy henefit from heromrng the d ~ r e r tohject of a memorable lecture on laboratory safety. This event occurred some 50 plus years ago when, as a graduate teaching assistant at the University of Minnesota, I was assiened resnonsibilitv for the laboratorv in" atruction in a first-vear chemistrv course. In retrospect. l can see that the professor was nut especially impressed by my competence, but rather his chief concern was the lecture section. He really did not expect much accomplishment in the laboratory. However, a t the time, I felt quite important in my role as laboratory supervisor, and I attentively examined the manual to select experiments t h a t looked interesting and somewhat matched the lectures in sequence. I had no previous familiarity with the hwk, but it was a standard laboratory text of the time, and the stockroom was able to provide all the reagents and equipment needed. Surely it would have been prudent for me to run through the experiments myself or, a t least, have talked ahout them with someone who knew the pitfalls as a result of prior experience. Good practice, of course, would have required all of the TA's involved to carry out the experiments before our students tried them, but in those days our work load included no time for TA training. Despite our innocent and uninformed approach to the laboratory periods, things went along astonishingly well until we came to the halogens, and I chose to assign "the preparation and properties of chlorine". The manual suggested using a hood for the preparations, and I had ohserved happily ~~
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Malcolm M. Renlrew's professional life has been dlvided between induslq and academe. On completing his PhD work at the University of Minnesota, he joinad the reSearch staff of the du Pont Plastics Depwlment, whase exceilent safety program made a lasting impression. In subsequent assignments in industry and at his alma mater, the University of Idaho, he has drawn upon that du Pont experience in encouraging safe laboratory practices. He is a long-term member of the ACS Committee on Chemical Safety and the Division of Chemical Health and Safety.
that our lab was equipped with small henchtop hoods at each student station. Unfortunatelv. the manual said nothine about cher!& the effectivenessof the hoods; had I done so, I would have found that ours were not functioning and in fact had never h ~ e n operable. My first awareness of this inadequacy in our ~hvsicalfacilities came midway through the first laboratory period, when the teaching assistant for the opening class that week came wild-eved to mv hasement office with this report: some of the student generators w r e highly effective in producing chlor~ne; the h o d s were nu1 effective in removing the excess. Students were teary-eyed; some were hanging out the windows coughing. Before I could respond to this melancholy state of affairs, the Marines arrived to save us all. Professor Lillian Cohen (Heaven bless her memmy!~came into the chem~stry building and smelled chlorine. Her unfavorable rerallectionr of chlorine dated bark to its use as a war gas by the Germans in the First World War, and she had never tolerated its use in any of Minnesota's classes. Hence, even though she had no direct responsibility for this course, she bounded up the stairs, brought the day's work to a close, and evacuated the laboratory. She then checked our students to make sure that none was suffering critically from the exposure. Next, she tumed her attention to me. With fire in her eyes, and a Marine sergeant's tone, she gave me the first intensive lecture on laboratory safety I had ever heard! I do not want to leave the imprershm that there had been no words of cautinn during my earlier chemistry training. I can recall, for example, being warned that when eleaning pipets with dichromate solution, one should avoid sucking up a mouthful. (Few, if any, academic people then used suction bulbs or asoirators for filline ninets.. and the rarcinogen~rpotential of chromium compuunds was not suspected.) Hut this was my very first lecture O H laboratory safety as a way of life. Well, times have changed; nowadays there would be lawsuits following a n incident of this kind' At the Universltv of Minnesota today, that lahoratory withihe decorative hoods has been remodeled into a modem facility with appropriate ventilation, and I know that their first-yearlaboratories now receive substantial faculty attention. But there, as elsewhere, undetected ~~
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hazards still have potential for damaging staff and students. Too often we fail to eliminate hazards until they are brought into the onen bv an accident. Constant vieilance and alertness to the changing scene are vital tu good 3afety program* It is deceptively easy to fall into cumplarency when a latwratr,ry course using "tried-and-true" experiments has gone along for years without any recognizable harm to students. Many of us were shocked when suddenly we became aware of the carcinogenic activitv of chemicals we had eommonlv used in our student laboratories. For years we had been warning students abuut the hazard of flammability in handling benzene, but we had not anticipated the impact of an OSHA ruling onmaximum tolerable exposure. (Initially a legal injunction blocked enforcement in the marketplace, and some knowledeeahle neoole held that the standard was " unduly strlct on the haGs of present physhnlugiraldata. But thisdid nut mean that prudent profesuoru c o ~ l dcontinue t o use henzene with beginning students in chemistry, at least in the facilities customarily available for first-year courses.) Some highly admired chemistry instructors hold to the view that we must teach our students to respect the hazard potential of all chemicals and to handle these suhstances safely. This seems to me defensible when instructing students in professional chemistry, especially in advanced courses. But for general students in a first college chemistry class, I am convinced that we must make full allowance for the chemistry student whose inent maninulations could expose himself or herself and
