Safety course for chemical technologists - Journal of Chemical

Content, audio-visual materials, demonstrations, assignments, and examinations in a safety course for chemical technologists...
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Safety Course for Chemical Technologists Kathleen A. Sinrpdon Northern Alberta Institute of Technology, Edmonton, Alberta. T5G 2R1 Canada

At the Northern Alberta Institute of Technology (NAIT) in Edmonton, Alberta, a twa-year program in Chemical Technology is offered to post-secondary students. The program consists of four terms, each 17 weeks long with an average of 30 hours of instruction per week. The intake is 60 students who are divided into two classes for theory courses. For the past several yearn, as part of this program, two courses in chemical safety have been given, one in the fust term and the other in the fourth term.As a guide to readers who might wish to set up similar courses. this oaoer first traces the hrstory of ~mplementationof these courses, and then delmeates their content

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Background In 1919, it was decided that a course specifically oriented to chemical safety would he a useful addition to the chemicaltechnology program. Initially run as a credit-noncredit pilot project in the term before graduation, the course has evolved to include 34 hours of instruction in safety in two courses. The addition of assignments and tests allowed grades to be given. During the first come, held in the first term, emphasis is placed on basic chemical safety such as the safe handling of flammable solvents and toxic materials, therefore orienting students to safety in the institute environment. The second course, in the last term before graduation, reviews the fust and offers more sophisticated topics such as radiation safety and risk analysis. I t prepares the graduating technologists to function safely in the workplace. As described helow, extensive use is made of audio-visual side, demonstrations, and hand-out materials in both courses. Kathlwn S l m p m received an Honors Bsc in chemistry from the Unlversiiy of Alberta In 1966 and a PhD in X-ray crystallbgraphy from me same university in 1973. high She has mum chmistry at ochocl. ooilege. and university levels over me last 20 yean both in Canada and a b r d . FM.the last nine years she has been an instructor in chemical technology at me Namern Alberta instilute of Tech mingy. Her specla1 leaching interests include analytical chemistry and chemical satety.

Journal of Chemical Education

Courm Content

I.fand-outs

Topics covered in the first course in chemieal safety are shown in Table 1while those in the second are listed in Table 2. In teaching chemical safety, a variety of instructional techniques are employed to stimulate and maintain interest and enthusiasm in what can sometimes be a dry subject. A hand-out complete with objectives is providedforeachtopic and is supplemented by lecture and discussion using incidents drawn from NAIT laboratories where possible. Every topic is accompanied by appromiate audio-visual material. demonstrations, and/or an assignment. A short multiple-choice test completes each topic. Guest speakers are used toadd interest and variety to the presentations.

Potential texts for a course in chemical safety to chemical technologists include books by Schieler and Pause ( I ) , Meyer (2), Turk and Green (3), and possibly the National Research Council's "Pmdent Practices for Handling Hazardous Chemicals in Labaratories" (4). The first two books are intended for fire fighters and so contain considerable elementary chemistry, which is unnecessary for chemical technology students. They do have end-of-chapter questions, however, which are useful for review. The latter two books are not set up as texts but as references; for example, they have no questions st the end of the chapters. The last-mentioned hook also seems to be well ahove the reading level of NAIT students. Since none of the available hooks appeared satisfactory, it was decided to teach our chemical safety courses without a textbook. As a substitute for a textbwk, written material on each topic has heen prepared at NAIT. This material serves as a review for the student of the material discussed in class. Over the taro courses, about 2W pages of material are provided. The first page of each hand-out ia a list of the objectives. As an example, Table 3 gives the objectives for

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TaMe 1. Topics for First-Term Courss

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IniraducUon and general safety orientation (1 h) Labelling (2 h) Fiammabb salvents (2 h) Fire edinguishen (2 h) Corrosives(2 h) Toxicity (2 h) compresaed gas- (1 h) Reanives (1 h) InsMious hazards (1 h) Prnenive clothing and equipment (1 h)

Table 2.

Topics tor Fourlh-Term Courae

Infrodunionand general safetyakntatian (1 h) Accident lnvsstlgatlon (1 h) Flammable solvent case studies (1 h) Canosive malerials case studies (1 h) Toxics case studies (1 h) Radioactives (1 h) Chemical stwage (1 h) Chemical dlsposal (1 h) Occupational HeaM and Safety An (1 h) Transportation of Dangerous Ooads A n ( < h) Electrical hslards (1 h) Risk analysis(2 h) Chronlc toxins (1 h) Ctyogens; safetyaudlts (1 h)

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Atthe endofthls lesson,thssMem will beable to: Detine burning. Name and discussthe three Interrelated compcnems of burning. Deflne and give lk-3 relevance of the following factm as they relateto burning: IgnRlon tem-we, f!ammable limlts, flesh point, tire point. Define flammable solvent. List four insMious hslards of sabems. Dl-s prwentatlve measures to wnirol flaw mabls harard in t e r n of the flre triangle. Briefly ~IWUSS fire flghtlng and spill conbDl as mey re- to tlammabls solvents. Use hazard infamation fa same common solvenhc.

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Demonstrations

flammable solvents. Students also receive a safety manual of about 25 pages with safety orocedures to be followed in the labaratoiies. An appendix to this manual lists all chemicals used in NAIT chemistry laboratories along with brief safety recommendations. To maintain a complete list of chemicals, a navel approach is taken: $0.10 is offered to the first student to find an omission and submit the appropriate data. So far about $3 has been paid out, mostly in the first year.

Materials Films and slide-tape presentations are essential to effective instruction in chemical safetv: ,. without audio-visual suooort.. safetv infurmation tends tc, remarn al,stract and lusrs relewnrg. I'reful film titles arc listed in Tablr I.S e ~ sof shdes m labelling. cum,sives, flammables, toxics, compressed gases, and storage are also available.' Specialized audio-visual materials may be available locally on topics of interest. It is advisable to check with regional occupational health and safety departments, fire departments, and environment ministries for useful items. For example, in Alberta, hydrogen sulfide is a major safety concern; thus;many films, videotapes, and written materials are readily available. Audio-visual

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Table 4.

The use of relevant demonstrations enhances the presentation of many topics in chemical safety. Of particular interest and value is an hour-long demonstration on the use of fireextinguishers (5).heldearly in the first term. In cooperation with both NAIT physical plant staff and the firedepartment, a large pan of gasoline is repeatedly set on fire and extinguished by the chemical technology students using a number of dry chemical and carbon dioxide extinguishers. For many students, this is their first experience with extinguishers and is the highlight of the course. This demonstration bas not been without problems. For example, postponements have been necessary due to wind, rain, and cold. Since NAIT isadjacent to the municipal airport, the dense smoke produced in the demonstration has had the ootential of disruotine.. air traffic. At,other I I S P ~ U I demonstration is one showing tlnshlmk and iu prevention usin,: rquipmenr rhuun in the figure. Respirator) equipment is demonstrated, air monitors are exhibited, induction and conventional motors are compared, liquid nitrogen provides experience with cryogens, and Styrofoam wig heads and paint are used to illustrate the importance of wearing safety glassa2

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Safety Filmsa

"Science: Live to Tell About It". 11 min, National Science Film Library, Mtawa "28 Crams of Prevention", 20 min, Fisher Sclentific co. "Safety: Isn't It Worth R?". 28 min, Fisher Scientific Co. "Using Fire Extinguishers the Right Way", 13 mln. Alberta Labw Library "Panable Fire Extinguishan". 15 mln, NAIT "Eye and Face RDteotion in the Chemical Labmatory", 14 min, Ed Fell Productions. Cleveland "Danger: H2S'. 15 min. Alberta Occupational Healthaod Safety Llbrary "ThreeMlnutes to Live". 30 min, Alberta Occupatianal Healih and Safety Library "it's Still Up to You". 11 min. NAIT "Black Monday", 20 mi". Canadian Film institute. M I ~ ~ i w a ~Ontario ga, "Nobody's Faun", 20 min, Alberta Occupational Health and Safety Library "Fire: Concepts and Behavior", 20 min, Alberta W Library "The Feminine Mistake", 25 mln. Alberta Lung As~oci~tion ',Using Compressed Gases Safely", 17 min, Math*son Gas Products, lnc. "HOW Safe is Enough?". 14 min. Whitesheti Nuclear Laboratories. Pinawa, Manitoba while my sovrceo are given tor the film listed. me reader is urged to seek out local suppliers since shipping and inevrance costs conhibuts significantly to rental costs. and since many suppliers are reluctant to ship out ot state or province.

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are connected by two vapor-transmlner tubes (D. E) to an ignition chamber (6).When a solvent such

vapor chambers and allowed to evaporate, the vapws will migrate toward the ignition chamber through the tubes. On reaching the ignition source, the vapors will ignite. and a visible flame front will travel back *rough the tube (flashback) and ignite the solvent in the source chambers. The addition of a flame arrestor in the tubing can prevent the flashback.

8s penlane is placed in the

Guest Speakers Depending on time allotted t o a safety course, and on the availability of appropriate speakers, the addition of guest lecturers canadd variety t o the course. Somesuggested speakers might be members of the fire de~artment.safetv officers from nearbv industry, people from the government (especially environment and occupational health and safety), workers' compensation board

Adapted from the film. "Eye and Face Protec-

tion in the Chemical Laboratory", available from Ed Feil Productions. 4626 Prospect St., Cisvaland. OH I J. T. Baker Chemical Co.. Phillipsburg. NJ

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(Continued on page A l l )

Table 5. Topics for Safety Papers Urea-formaldehydefoam Mercury and its compounds

personnel, and public or occupational nurses. I t is usuallv best to ask euest sueakrrs to rover a specific topic.and it is preferable to meet helurehand toorient them to the students and to the course. Assignments Assignments provide students with the opportunity to pursue same aspects of chemical safety in depth; in addition, they help the instruetor in assigning grades. Each student in chemical safety receives essignments based on an individualized set of chemicals. In the first course, assignments include the analysis of a label, an analysis of a hazard, a literature reference project, a review of a safety-related article, and the preparation of a hazardous materials date sheet. The second course assignments involve a repmt on some particular aspect of chemical safety, as well as group work on case histories, a safety audit, and a worksheet on a film. The "Analysis of a Label" assignment has each student given a different label, with comment required on the adequacy of the safety information on that label. The "Analysis of a Hazard" assignment requires a onepage summary of profirties andhazards for a uniquely assigned chemical that has been banned from Alberta schools. The literature reference project familiarizes the student with the safety-related material contained in the learning resources area. For the article review, the student discusses one assigned article from the "Safety in the Chemical Laboratory" feature of this Journal. A blank standard Hazardous Material Data Sheet (HMDS3is provided for the final assignment in the first course with each student preparing the sheet for a specified commonly used chemical. These sheets are then duplicated, and the resulting set of HMDS's serves as a useful reference in future courses. In the second course, the major asaignment consists of a technical report of at least 10 pages in which the student examines one asuect of chemical safetv. Table 5 lists the topm that have been used. Ses,eral a a n i ~ ments are h s e d on oral and written presentations made by groupsiflfstudentson some. what humorous case histories that are fietitious hut based on fact. These case studies are primarily used to review first-year course material. A typical example is the following:

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D. Caffeinated, a technician at the Careless Chemical Company, prepared a cup of coffee in a 250-mL beaker and set it momentarily near the sink. Next to the sink was an unlahelled 250-mL beaker of used (darkened) chromate cleaning solution which D. picked up instead of the coffee and sipped. VNDIeach case study, the group must anaIvze the incident, give the direct cause. R I W some uf the indirect causes, and suggest ap-

'OSHA. Form 20 (Material Safety Data Sheet) or similar.

Carbon tetrachloride Chromium and ik compounds PCB and PBB Lead and its compounds Vinvl chlwide m m e r Emers and peroxides Cnforineand chiorinbgenarstmg compounds Transpwtation of chemicals Benzene Mutagens and teratogens Safe handling of carcinogens BLEVY

Ethylene dibromide Dioxin Acetylene Phenol and phenolic compounds Organophosphate pesticides Dyes-coal tar and aniline Formaldehyde Safe disposal of radioactive materials Hydrogen sulfide Hydrogen cyanide and other cyanides Anhydrous ammonia Dermatitis in chemlcal wwkers Sulfur Cadmium and its compounds LBSBTS

Risk assessmem of chemical hazards Asbestos Chemical SensitIration and chemically induced hazards

Microwaves. VTR's. ,V,and iRas satety problems Critical Survey ot sodrces 01 intmmlion In chemical safety Methylisocyanate Fiuorinated hydracarbons Phosgene Problems with chemical dust Aluminum Waste dispwai In Alberta Safe handling of explosive materials Carbon monoxide Arsenic, antimony, and meir compounds Alternates to the LD5. test

propriate action for the immediate situation and for the future. The safety audit consists of a four-page check list of safety items for a given laboratory room in the institute.' Extra blank check lists me available so that students may aaresx their future place of employment if they wish. The assignment connected with audiu.viwa1 material haa students watch a film and then answer a series of questions hased on the film. Some of the films listed in Table 4 have been used for this assignment. ~

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Tesb and Examlnatlons To complete each topic, a short multiplechoice test has been prepared. The questions are hased on the obiectives orovided with the handout. As asample, forthe objeetive,

'Similar to the Safety Inspection Report in J. Chsm. Educ. 1981, 58, A3. (Continued on page A14)

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Number 1 January 1987

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acceptance a t NAIT. These courses are a unique part of the curriculum since they can he used from the first time a student enters rhc lsburatory. as uell as after t h e y gradua t e . Hoth students and mstrurturr are most poririw abuut rhe course. A> proof of t h e i r effectiveness, the number of minor accidents has lessened, the number of safety related questions in class and lab has gone up, and overall safety awareness is high. With increasing knowledge of chemical hazards, in the near future it is expected that courses in chemical safety are likely to he demanded both by students and their emplayers. Our chemical safety courses a t NAIT can be used to advantage as a model in planning your own approach t o education in chemical safety. ~~~~~

The student will be able to describe the signal words used in connection with the hazard classes. The multiple-choice question is a labrl tusrr the wmd DANGF'K! i n connection w i t h t h e hsrard uf a chrniirnl: a. This is the highest Level of warning. b. This is an intermediate level of warning. c. This is the lowest level of warning. d. The substance should only be used in a fume hood. e. The substance should be refrigerated a t all times. \\'hen

These tests take five minutes or less to complete. At the end of each course,a one-hour final examination is held. Part of this test is a set ofTRUE-FALSE, correct the FALSE questions to survey the overall safety knowledge ofthestudent. As well, several questionsare asked that require more detailed knowledge. Far example,

Discuss fires and their control. Include the fire triangle, the classes of fires, eatinguishing agents for use with each type of fire, and the correct way to use a fire extinguisher. Finally, expected behavior in certain hazardous situations is explored through questions such as There is a strong smell of ether in the laboratory on your return from lunch. What is the primary hazard? What actions will you take immediately? Why?

SupplementalMaterials Often, in addition t o the prepared handouts far each topic, there are magazine or journal articles particularly suited to the subject. As examples, when discussing chemieal-waste disposal, students read an Atlantic article (6) and one from Chemical Engineering (7);while on the subject of toxicity, this Journal has provided two relevant articles (8, 9). The National Safety Council (10)haspreparedmany datasheets, same of a general nature such as "Flammable Liquids in Small Containers". These make excellent additionar readine. A welltnain~ainrdnewspaper-clipping lile is nlwa guod iourre of current lucdl marprinl. ~~~

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References There are many useful references in the field of chemical safety. Some that have been useful here s t NAIT are primarily lists of chemicals and their hazards (11-151, while others provide information of a more generalnature (16-21). Many references are expensive, so care should he exercised in choosing up-to-date and comprehensive reference materials. Concluslon The two courses in chemical safety described above have met with enthusiastic A14

Journal of Chemical Education

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11) Schieler, L.; Pause, D. "Hazardous MateriaW Delmar: Albany. NY. 1976. (2) Meyer, E. .Themistry of Hazardous Materials"; Prentiee-Haa: Englewmd Cliffs, NJ, 1977. (3) Green, M. E.: and Turk, A. "Safety in Working with Chemicals': MacMillan: New York, 1978. ( I , National Research Council, "Prudent Prsetiea fcl Handling Hazardous Chemieala in Laboratories"; National Academy: Washington, DC. 1981. (5) Wilbraham, A. C. J. Chem. Educ. 1978.55. A405. (6) Brown, M. H. Atlantic 1979,244.33. (71 Machie. J. A,: Niesen, K. Chrm. Eng. 1984.91 IAug. 61.50. (8) Carter, D. E.;Fernando,Q. 3. Chem. Educ. 1973.56, 2%. (9) Carter, D. E.; Fernando, Q. J . Chem. Educ. 1979.56, LO"

L9%. Steere, N. v.. Ed. "CRC Handbwk of Laboratory Safety"; Chemical Rubber Co.: Cleveland, OH, 1971. Brethonck, L,"Havuds in the Chemical Labaratow", 3rd ed: Royal Societyaf Chemistry: Loodon, 1981. Lenga, R. E. "The Sigms-Aldrich Library of Chemical Safety Data: 1st ed.;Sigma~AldrichCow: 1985. Armour. M. A,: Browne, L. M.; Weir, G. L. "Hazardous Chemicals loformation and Dispoasl Guide", 2nd ad.; Univer~ityof Alberta: Alberta, 1984. Lofevre, M. J., "First Aid Manual far Chemical A a i ~ denfs"; Dowden. H u t c h i n ~ nand Ross: Stroudahuw, PA, 1980. McCann, M. "Artid Beware": Watson-Guptill: New York. ,979. Gerlouieh. J. A: Doms. G. E. '"Better Science Through Safety"; low* State University: Ames, IA. IW,

(19) Steere, N. V. "Safety in the Chemical Laboratory"; ~ivkionofChemim1Edumtion: Easton, PA: Vols. 1-

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(201 Renfrew, M. M."Sefety in the ChhmiiilLibarbotfw"; Division of Chemical Education: Easton, PA; Vol.4. (21) ACS Committee on Chemical Satety "Safety in Amdemic Chemistry Laborstoria", 4th &.; American Chemical Society: Washington, DC. 1985.