DCHAS-L Discussion List Archive
Date: Fri, 6 Apr 2007 13:08:10 -0400
Reply-To: List Moderator <ecgrants**At_Symbol_Here**UVM.EDU>
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From: List Moderator <ecgrants**At_Symbol_Here**UVM.EDU>
Subject: 4 RE: [DCHAS-L] Managing class lab wastes
Four replies I've received so far to yesterday's questions. More
welcome.
Thanks to everyone who's responded.
- Ralph
From: "Klotz, Ann"
Date: April 5, 2007 4:12:49 PM EDT
Subject: RE: [DCHAS-L] Managing class lab wastes
Things that work for me:
Waste handling instructions are in written into the procedure for the
lab AND the instructions are also written on a white board in the lab.
--Same whiteboard each week. Students know where they can find out how
to handle waste without asking the instructor.
With multiple sections of the same waste, I try to have only the waste
for that particular week in the lab. It is moved to 90/180 day storage
before the next lab experiment begins. If there are multiple waste
streams and they are incompatible, that is a taught as an important
concept of the lab work. Sometimes students are required to show the
waste to the instructor before adding it to the waste container.
I find there are fewer spills when students are provided wide mouth
bottles then when asked to use funnels and narrow mouth bottles.
Teaching students why a particular waste or waste stream is hazardous is
VERY helpful.
A sample from the laboratory procedure:
Cycle of Copper Reactions
WASTE: Acetone and nitric acid should not be mixed. Use separate
bottles, each labeled "HAZARDOUS WASTE". Acetone is flammable and must
be removed for disposal. Solutions of nitric acid, sulfuric acid or
sodium hydroxide are corrosive and must be removed for disposal.
Ann
==
From: "George H. Wahl, Jr."
Date: April 5, 2007 4:39:24 PM EDT
Subject: Re: [DCHAS-L] Managing class lab wastes
Ralph,
I've been out off the lab for a few years, but before I left I
changed our undergraduate Organic labs to "Micro-scale". [ It's NOT
truly "micro", but we typically reduced quantities from about 25-50
mL, to 1-3 mL. The accompanying reduction in chemicals purchased and
waste generated caused about an 80% reduction in the budget for these
large labs.
> - Should classes be provided with a separate waste container for
> each session of the same lab so that the likelihood of incorrectly
> mixing wastes is minimized, or is that more confusing than
> clarifying in terms of what goes where?
For sure, each lab ( that is each Experiment! ) should have unique
lab waste containers. Sometimes more than one for a lab since
occasionally there's more than one waste. Our HazWaste folks are
delighted with this segration, and it has caused us no problems
whatever.
> - Are funnels a help in filling a container or do they cause more
> spills when they are overfilled?
Funnels are a definite must. We also demand that the containers be
kept closed, and in a hood. The funnel is therefore found on an
adjoining plastic secondary containment "platter".
> - What kind of training is provided to TA's in terms of helping
> them appreciate the importance of good class lab waste management?
I varies, but quoting to them the costs involved in cleaning up a
spill, or in disposing of waste created by a spill get their
attention. Also, we use our own 'home-grown' lab books, and these
contain specific guidance regarding haz waste.
HOPE this helps.
george
==
From: rudikazudi**At_Symbol_Here**aol.com
Date: April 5, 2007 5:10:22 PM EDT
Subject: Re: [DCHAS-L] Managing class lab wastes
Ralph,
In our instructional labs we provide individual labeled, collection
bottles sized appropriate for the volumn of waste anticipated. At the
end of each lab session, the waste collected is transferred to a
larger container sized for a week's worth of that waste (again the
container is pre-labeled exactly as the bottles in the lab). At the
end of the lab week, the waste is logged in at the chemistry waste
storage area.
This procedure has worked well for us at all instructional levels and
makes waste documentation much more efficient.
Mary Ruth
†
Mary Ruth Andrews
6013 Cumberland Rd. S.
Mobile, AL 36608
251-342-2312
==
From: Elizabeth Gregory
Date: April 5, 2007 6:10:11 PM EDT
Subject: RE: [DCHAS-L] Managing class lab wastes
Hi Ralph,
I'm the person who provides waste containers (labelled) for our teaching
labs, and I transfer them to our CAA when they're full. I use the same
system that my predecessor developed. Here's what we do:
1) Each individual experiment (NOT section - if there are four groups
of students doing the exact same experiment, they get the same
bottle!) gets its own waste bottle, whose size is picked such that it
will contain all of the waste from that experiment. This ranges in
size from 100mL (for the Pd/C catalyst used in Organic's
hydrogenation experiment) up to a 20L drum (used for the gen chem
Kinetics experiment). The chemistry professors in my department are
very good about giving me any bottles they empty in the course of
their research, so I normally have a good stock of various sizes.
When choosing a bottle, I err on the "better too large than too
small" principle. Sometimes I've completely overestimated what
they'll need, and in those cases I just hold onto the bottle until
the experiment is run the next year (I never go over 55 gallons of
waste in my SAA). This also makes it easier for me to "fix" the waste
content list when they generated twice as much waste as I expected -
at least I can narrow down what the possible added stuff is to one
experiment!
2) Two years ago I tried to restructure my organic chemistry waste
bottles. I put one 4L bottle out at a time, and it was used until it
was filled (all of the wastes from all of the organic chemistry
experiments was compatible). This was an utter disaster - I can't
have the students log what they put into the bottle, as they can not
accurately estimate volumes (or even tell me what's in their test
tube!), so I had the instructors log in the amount that was added at
the end of the section. I ran into two major issues here. First, the
instructors themselves often forgot to fill out the sheet, so I would
walk in the next day and see a 4L bottle full, with the log saying
there was only 250mL of liquid in it. Second, the bottles would
invariably become full in the middle of a section, leading to
overfilling, and a huge mess to clean up.
3) I absolutely use funnels. Every so often I forget to put one out
with a waste bottle, or a student takes it back to their bench, and
on a couple of these instances they have made such a "missed the
opening" mess that I had to pour the secondary containment bin off!
As mentioned above, I do my best to make sure that, if anything, I
provide a bottle that will be large enough for them, and I have the
lab assistants check them at the end of lab, and put out an empty one
if it's getting too full for the next section.
4) You didn't ask for this, but here's how we inform the students of
how to dispose of stuff:
a) It's written in the instructions for the experiment
b) It's given to them verbally in the pre-lab lecture
c) It's posted (on the same color paper as the waste label) on the
fume hood that we use for the SAA
d) Our organic chemistry professor also requires them to transcribe
the waste instructions into their lab notebook.
5) In terms of training, they get a bit of it during their OSHA
training every year as a starting point. They never make a waste
determination in the course of their job (they are all undergraduate
students working under an instructor who is present in the lab). This
means that all my lab assistants need is to be told how to deal with
the wastes generated in the experiment. I provide them with a copy of
the lab manual, and they can also look at the instructions on the SAA
hood if they need during the experiment.
Hope this helps, and if you have any suggestions for improving my
system (especially if you know how to get students to stop putting
the non-hazardous aqueous workup waste into the organic hazardous
waste bottle!!), I'd love to hear it!
Elizabeth Gregory
Laboratory Manager
Department of Chemistry
SUNY College at Brockport
Room 230 Smith Hall
Brockport, NY 14420
(585) 395-2210
Fax: (585) 395-5805
Email: egregory**At_Symbol_Here**brockport.edu
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