When I was a graduate student in Cambridge 1991-94 any apparatus left running overnight needed to be inspected by a technician and display a signed and dated placard during overnight operation. I believe the inspections focused on making sure there was adequate cooling, pressure relief, and secure clamping etc. Labs were closed to personnel after 12 midnight.

> On Feb 12, 2019, at 11:08 AM, DCHAS Membership Chair <membership**At_Symbol_Here**DCHAS.ORG> wrote:
>
> I know that several campuses and/or chemistry departments have developed placard systems for chemical operations which are left unattended. The purpose of these signs is in case an incident occurs when the person who set up the process is not immediately available to answer questions about it.
>
> I am interested in developing a list of these efforts in order to understand what level of detail people have determined is best suited for their needs in this respect. If you have developed a formal system that serves this purpose, I would appreciate it if you would share an URL to the form or a PDF copy of the form. I'll provide a list of what I receive to the list later this week.
>
> Thanks for any help with this.
>
> - Ralph
>
> Ralph Stuart, CIH, CCHO
> membership**At_Symbol_Here**dchas.org
>
> Membership chair
> American Chemical Society
> Division of Chemical Health and Safety
>
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