We have a completely open and shared upper level laboratory. We teach 2 courses per semester in the laboratory, sometimes, but not usually, with 2 classes in there at once (organic, 2 semesters, analytical in the fall and inorganic in the spring). The students spread throughout the lab, with mostly shared glassware, chemicals, etc. Needless to say, it can get ugly in there.
How do you manage the cleanliness issue? With a completely open lab, it is very difficult for each student to have an assigned workspace, and with no assigned glassware or desks, it is very difficult to get the students to have ownership of the equipment.
Now, I completely understand that occasionally the students will accidentally forget to clean up. But what do people do to provide both carrots and sticks for lab cleanliness, lab citizenship, etc.
Another thought to increase ownership would be to have lab clean-up at the beginning and end of every academic term. This would allow all the students in a given course to familiarize themselves with the lab, its equipment, and the expectation of cleanliness from the start, with the knowledge that they'll have to return it to its original "pristine" state at the end of term. But, this may be a naive approach, and would likely work best for smaller classes where resources are limited enough that everyone is aware of how important it is to keep them in good condition. Perhaps some sort of lab "KP" duty would be useful; everyone has one week (or day) where it's their turn to come in for 1.5 or 2 hours and do whatever lab clean-up is needed, whether it's cleaning out the glassware that's been soaking in a base-bath, or restocking common chemicals--whatever needs doing, essentially. Students could space out over the term, and have 2 or 3 people on duty each week after the lab sections. This idea would require some level of faculty input, but not as much supervision as a big clean-up day.
Other ideas for smaller courses include end-of-term rewards for keeping the lab in great shape all term. Free food, performing a series of cool demonstrations, or even giving students opportunities for a cooler final lab exercise are things that could be both an incentive as well as a learning opportunity. Although if I had an awesome lab and a so-so lab to offer my students, I'd probably want to pick the awesome one regardless of how messy their lab was. ...Unless the awesome lab required a lot of clean up. Then they'd have to prove themselves first. So, while highly hypothetical, that's another idea that might work. Good luck.