A guest post by Ralph Stuart, secretary of the ACS Division of Chemical Health & Safety.
Last week's DCHAS symposium on Safety in Undergraduate Teaching included several interesting presentations on effective ways of teaching lab safety, particularly chemical risk assessment, for both undergraduates and incoming graduate students. It was heartening to hear about class safety efforts that went beyond a focus on personal protective equipment to include teaching the logic of safety rules in the class lab and how these change as the work being conducted changes. The impact of this approach on student learning was also discussed.
Somewhat more surprisingly, core questions about the teaching laboratory were raised by several of the presentations. These included:
- Does the teaching lab mission include providing students with experience in working successfully and safely with hazardous chemicals?
- And if it is, is this aspect of the teaching mission being lost as less hazardous chemicals are being increasingly used in teaching laboratories?
- And if the use of hazardous chemicals isn't part of the teaching mission of general and organic chemistry labs, where are students going to learn how to work with hazardous chemicals safely?
Feedback from people who hire science majors suggests that students are expected to have basic laboratory safety literacy when they take a job related to their major.
Following this theme, presentations highlighted the difference between the tools and techniques of historical descriptive chemistry and the theory of molecular-level activity that is focused on chemistry textbooks. One presentation mentioned a recent article in the Journal of Chemical Education that suggests that the current undergrad teaching lab experience provides students with neither improved understanding of molecular theory nor increased comfort with working in a chemical laboratory.
However, an off-hard remark by one presenter raised another question in my mind that no one remarked on. He mentioned that his institution was in the planning stages for new chemistry teaching laboratories that would include a fume hood for every student team. This is becoming an increasingly common design strategy in higher education. As a result, many teaching laboratories have in the neighborhood of 40 air changes per hour (ACH); this rate is many times that generally required by safety considerations in the research laboratory (between 6 and 12 ACH are considered appropriate there).
This design habit raises concerns about ventilation noise (especially important in teaching labs), as well as about the financial and carbon costs of heating and cooling these labs. Another important question to consider, more directly related to the topic discussed in the symposium, is whether students are developing chemical handling habits based on over-ventilated teaching laboratories that will not serve them well when they reach other laboratories. My experience in responding to complaints about inadequate ventilation in research laboratories is that essentially all of these complaints are rooted in poor practices in using fume hoods and/or the result of sloppy housekeeping of odoriferous chemicals outside the hood. These practices many not be noticed in a teaching lab, where ventilation rates are so high that the difference between being inside and outside the hood can sometimes be difficult to discern.
The challenge of defining the 21st mission of introductory chemistry teaching laboratories, in which the majority of students do not expect to pursue chemical research as a career path, but are likely to use chemicals as part of their science, are significant. The teaching lab role in teaching chemical safety is assuming greater importance, as indicated by a recent analysis of the ACS Committee of Professional Training's guidelines for chemistry programs. However, opportunities for better understanding how to implement these criteria remain.