Improving Shop Safety

On April 13, 2011, Yale University senior Michele Dufault, an astronomy and physics major, died after her hair caught in a lathe in a university machine shop. In response to the incident, Yale initiated a review of its policies concerning student access and use of machine shops and released its updated rules over the summer. The new policies divide shop tools and equipment into categories based on their potential hazards, allow student access based on those categories, largely prohibit working alone, and require safety review of machine shop projects before students can begin work.

The new policies are an objective and risk-based approach to machine shop access and safety, says Laurence Doemeny, chair of the American Chemical Society Committee on Chemical Safety. After Dufault’s death, Doemeny informally surveyed a number of university shop policies available online. Yale’s updated program is similar to other shop programs he can recall, he says. Doem­eny also notes that the policies on not working when fatigued or alone and the requirement for project risk assessment are good practices for chemical laboratories.

The committee that developed the new shop policies was chaired by Steven M. Girvin, a theoretical physicist and Yale’s deputy provost for science and technology. “Our first guiding principle was that shop, fabrication, and materials work play a really important role in the education of many of our students,” Girvin says. The group also wanted to instill a culture of safety in the school’s machine shops that wasn’t just about checking off boxes, Girvin adds.

Shop tools at Yale are now divided into five categories, from low-power hand or small bench tools, such as soldering irons and heat guns, up to large industrial tools, such as full-sized milling machines or metal lathes. The committee sought input from users, faculty, and outside experts, and the classification process was relatively straightforward, Girvin says, although he acknowledges that it’s a first attempt. “It may still be something we want to refine as we put it into practice and learn more about the actual implementation,” he adds.

Before students can use campus shops, they must take a training course. They also have to sign a code of conduct agreement that stipulates which tools they’re allowed to use. Access to those tools then depends on the type of student and a particular tool’s classification.

Anyone can access and use category one, low-power tools at any time. Undergraduates using category two, medium-power tools must have at least a peer “buddy” with them who also has the appropriate training for the tool in question. Buddies “must be within immediate sight and sound of each other and familiar with emergency shutoff of the equipment,” the policy says.

For categories three and four, powerful portable and small benchtop tools and light industrial tools, undergraduates must work under the supervision of a monitor or supervisor. Monitors can be experienced graduates students, postdoctoral researchers, or staff who have been trained and certified as monitors by Yale’s Environmental Health & Safety office. Supervisors are staff or faculty with professional-level training or experience. To use category five, large industrial tools, undergraduates must be overseen by a supervisor.

Graduate students, in contrast, can use category two tools alone. For tools in categories three to five, they must at least have a peer buddy with them. Postdocs at Yale are considered to be faculty, who fall under separate requirements for training and experience.

Girvin acknowledges that in some cases “graduate students were undergraduates three months ago. There is not a rigorous mapping between skill level and age or title, so one has to be a little cautious.” Shop supervisors will need to verify that everyone using the shops has the appropriate experience and training for what they’re trying to do, Girvin says.

And there will be faculty oversight as well, through a now-required safety review before students start working on projects involving category two and higher tools. The reviews are to encompass not just tool use but also the possible hazards of the materials used and the risks of using the part after it’s made, Girvin says, emphasizing that Yale sees the review as an important “teachable moment” for students. This semester, the student shop policy committee is working on developing a uniform document that will cover all of the considerations but avoid making the review “some extremely onerous thing,” Girvin says.

Other parts to the new policy include a prohibition on working in shops after midnight, which is probably the biggest change overall for students, Girvin says. Shops will also restrict access at either the tool or the room level. At the room level, access will be controlled through university identification cards—and the buddy system will be enforced by various methods, including a card access system.

The other big change may be in shop supervisor workload. “It’s still early in the semester and the demand for after-hours supervision tends to peak in the last few weeks,” Girvin tells C&EN. The university may need to supplement staffing, but the details have not yet been worked out, he says.

Chemistry and chemical engineering professor Kurt W. Zilm, who oversees the Yale chemistry department shop, agrees with Girvin that the biggest change in terms of day-to-day shop operations will likely be the need for increased supervision of undergraduates. The shop has always prohibited working alone—“If I ever saw anyone in there by themselves, I booted them out,” he tells C&EN—but it was through a buddy system rather than the new buddy/monitor/supervisor hierarchy. And despite the prohibition, Dufault died when she was working alone in the chemistry shop at night. A new card-reader system and video surveillance will help to ensure that rules are followed, Zilm says. The shop is also upgrading much of its equipment and adding emergency shutoffs.

Other schools have been interested in Yale’s new shop safety program, Girvin says. Yale made the policies public both so other schools could use them as a tool and so Yale could get feedback on them. “We want to learn from best practices at other places,” Girvin says. “Safety is a very, very important topic for any institution involved with education, and it’s a continuing effort to constantly pay attention to safety and promote a culture of safety.”