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edlted by
MALCOLM M. RENFREW University of ldaho MOSCOW, ldaho 83843
A University-Level Course in Laboratory 'Safety by George G. Lowry Western Michigan University, Kalamazoo, Michigan 49008
For the past five years, the Chemistry Department of Western Michigan University has offered a one-semester-hour course in chemical laboratory safety for upper level students. Prior completion of 24 semester hours of chemistry is required, so that enrollees normally will have completed a t least one semester each of organic and physical chemistry and of quantitative analysis. The course is a degree requirement for allgraduate students in the department, and a numher of undergraduates elect it. It was necessary to develop this course "from scratch", as no textbook or outlines were found that would be suitable a t the desired level. Various aspects of the resulting course are described here for the information of others who might contemplate offering such a course.
Aims of the Course In developing the course, i t was quickly decided not to make it a semester-long sequence of safety rules or a detailed summary of governmental regulations. Many of the basic safe-warkinrcrules are alreadv familiar to the students (whether or not the; are fully appreciated and observed), and more specific rules vary widely from one laboratory to another. Many governmental regulations are obscure, or obscurely stated, and they are frequently changed, so rote learning of such material would seem rather pu~nrlrss. The appronrh ndoptrd is toconVd~r"iafe" workrnr" cond~r~ansar thwe in whirh the risk of damage to person or property as a result of potential hazards is acceptable. The main thrust of the course is to build in the students a good understanding of the nature of potential hazards and the ability to assess the artendanr rlski undrr various condirions. Thourh a decision ac u, what risk%m~ghthr conskltred acce~tablela ha%icallvsubiecrtve, numerous d i s c u h n s of this conceptare interspersed among discussions of specific hazards. One potential problem of such a course is that students might develop a paranoid fear of lahoratory hazards as a result of the detailed discussions. Indeed, there have been two or three students who have each developed an unnatural fear of a particular potential laboratory hazard. I t is difficult to say whether this might have occurred if they had not taken the course. Fortunately their admitted fears did not seem t o be crippling, in that they were still able to function in their laboratory work. The philosophy impressed on the students in this regard is that there is no chemical reaction that is inherently safe or unsafe, but that any chemical reaction can he carried out in either a safe or an unsafe mnnner. lr is thrn the purpose of safe workma practice to be able ru ~ e l r r tthe appruprlntc procedures. Based on the concepts outlined in the above ~aragraphs,the specific purposes, 01 (Continued an page A2361 ~~~
George G. Lowry Western Michigan University Kalarnazoo, MI 49008
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Volume 55, Number 5. May 1978 1 A235
Safety
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goals, of the course are to: 1)' Arouse in the student an intense awareness of safe working habits and conditions; 2) Arouse in the student an increased awareness of the effects of his or her work on the environment and on innocent bystanders should adequate safety precautions not be taken; 3) Introduce the student to the nature and breadth of various legal constraints placed on chemical work by legislation and by executive orders from various governmental agencies; 4) Develop the student's ability to obtain information regarding all types of safety hazards for any given chemical compound or reaction system; 5) Develop the student's understanding of the scientific principles involved in many types of laboratory (and plant) safety hazards; and 6) Introduce the student to methods of estimatine the severitv of ~ o t e n t i a l the literature.
Textbooks It would have been convenient to organize the course around a suitable textbook if one
but it does not have the depth and hreadth of coverage desired. For the past two years, the assigned "textbook" has been the reprint volumes from this Journal (4). While these three hooks are not edited into acoherent textbook, they contain adequate material for the course. Unfortunately, these books are expensive, as the bookstore must buy them a t list price and then mark the price up further. However this collection of articles gives adequate breadth and depth of coverage; they probably will continue in use, a t least in the near future.
had been available, but such was not the case. Though an extensive search has not turned up a satisfactory textbook, it was considered important that the students have written material tostudy. Experience with the use of cited journal references or of library reserve hooks has been unsatisfactory for any except small classes. (Enrollment in this course has been between 20 and 40 students.) Of the books examined, four seemed potentially useful. One was initially adopted with some satisfaction but was later replaced with another. The closest thing to a satisfactory textbook. in the usual sense. seemed to be "Safetv and Accident P r e v ~ n t i min Chemical Operations", by Fawcerr and Wood ( 1 1 . Ewn this excrllent h~okgirtuinadrquatrfrrorrnrnt some subjects, which is not in itself fatal, but the hook was felt t o be just too expensive to use as a text for a one-credit course. However, it contains excellent backgroundmaterial far the instructor. The "Handbook of Laboratorv Safetv" . (2). . . though nut urltren np n t e x t h ~ t k is , an PRcellent reference h o k for rhemkts, and the d r r r r i p t i ~ rmawr~alit nmtaini n ~ l dIre adapted to the purpose very well. However, its high price tag caused it to be eliminated from serious consideration. The first hook actually adopted for student use in the course was Quam's excellent oaperhack hook (3,. For ;uch a small book', it conrain4an amazing anmunt of usrful iniormntim. It is primnrdy nmmpcndium ofrolrs. properties, descriptions of protective equipmmr. rtc.. though, and contains verv l~rtle discussion of the scientific prinr~plrs onvolred. For lu; rrurwse the hook I - errellent,
Organitallon of the Course
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A236 / Journal of Chemical Education
The first few class meetings are devoted to introductory and review material, for which the books are not used. In particular, i t has been found necessary to review some elementarv. ohvsical chemistrv. Thouah the . . studenti are iam~linrwuh gas laas, thcrmorhemistrv and rrlnted material. mnnv do not have a good w r k ~ n gknowledye of rhrse subjects. Specific areas reviewed include the following. Some students seem mystified as to how to compute vapor concentrations in rngIm3, given the concentrations in parts per million (this seemsto be their first exposure to such common practical units). The idea of balancing equations for, and performing thermoehemieal calculations on, incomplete combustion reactions is another stumbling block. The actual use of a temperature-dependent functional form of specific heats seems to be a strange concept to some students even though they have been exposed to it nrrviouslv. Also. i t takes a little oersuasion ~~, to convince students they can use the Clausius-Clapeyron equation to interpolate values in a table of vapor pressures of liquids. Finally, the use of simple thermochemistry to compute approximate adiabatic flame temperatures is anew application that is included in introductory material. Followine the introductorv material, the remainder i f the course outline in the &hle is followed using the assigned readings in the reprint hooks. "Primary References" are particularly important for completing the assigned work of the course satisfactorily. "Secondary References" include material that is related to the particular subject but is simolv for reference or is somewhat s~ecialimd. Some articles a ~ "d to v several tr&cs. An idea of how the topics are stressed in the course can best be obtained by examining the problems and questions listed below, but a few comments are offered here regarding treatment of some of the topics. Toxic and Respiratory Hazards are somewhat overlapping subjects and are treated as such. in addition to seoarate treatment of other types of toxic exposure and physical asphyxiation. Problems of analyzing and monitormg airborne toxic substances are dealt with, as are problems associated with fume hoods. Also, various types of gas masks and respirators are described in detail and demonstrated. The physical chemistry of chemical decomposition and combustion is discussed in detail. The use of a simple differential thermal analysis measurement t o screen new compounds for potential instability is de~~
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Schedule and readlng assignments for laboratory safety course
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Mllrnker
of Days
Referencesa Topic
Primary
Secondary
General lntraductian mermochemistry and Gas Laws Adiabatic Flames Toxic Hazards Respiratory Hazards Chemical Stabill Fire and Flammabillly Radiatlon Hazards Electrical and Mechanical Hazards Storage. Handling and Disposal 01 Chemicals Protective Equipment Safe ExperimentationPsychological Condition and Planning
Roman numerals refer to me volume numbers of me text (4). and Arabic numerals indicate me pages on which m e assigned articles begin.
srrihed. and examples Croups oi unstnb.r ccmqwun~lsare given. Iinder Rsdtatron Harardr, all types of rodioactivity, various types of electromagnetic radiation, lasers, sound, and particle accelerators are discussed. Various types of monitoring and controlling instruments are discussed under Protective Equipment, in addition t o the more usual fume hoods, glove boxes, gloves, face shields, explosion shields, ete. Obviously it is impossible to discussany of the topics in great detail within the allotted time, so brief discussions and examples are given together with suggestions for more detailed study. Nevertheless, the students are introduced to several important topics that are new to them, as well as to new ways of considering familiar topics. Students have also been very interested in dircurtmr many news item- ahout pdlurion. induirrial accidents, PI).\ drcisions, etc.. nz they arc related I
