Chemical Safety Violation in Litho

Mary Tang mtang at
Mon Aug 16 12:51:59 PDT 2004

Sigh....  Not again...

There was a chemical safety violation discovered this morning in the
litho area.  You are receiving this note because you enabled one of the
manual coaters (or svgcoat track #1, which can be used for manual coats)
some time between Friday at 5 pm and this morning.  In as broad sweeping
campaign to eliminate chemical safety violations in the lab, I am

What happened:

A yellow hazardous waste bag, without a label, was found in the regular
trash can (NOT the enclosed solid solvent waste can) across from the
litho solvent bench.  Jorge, the custodian, was doing his regular
cleanup, and complained about the smell.  Do I have to tell you how
completely and utterly irresponsible this is?  I mean it's bad enough to
subject your fellow labmates to chemical exposure, however inadvertent
-- but at least he/she probably has some fair idea of what it might be
and what to do about it --  it's just completely appalling that someone
would be so careless as to subject the custodial staff to this.

Solid  waste that is contaminated by standard solvents or photoresists
should be bagged under a ventilated area and placed in the solid solvent
waste can.  Non-standard or halogenated (i.e., chlorinated) solvent
waste should be double-bagged separately and tightly in yellow hazardous
waste bags, and the chemical contents listed on the hazardous waste tag
which you attach to the bag.  The bag should be placed in the
appropriate area for pickup.

If the solvent waste can is full, then double-bag your waste in yellow
hazardous waste bags, LABEL it, and place in the appropriate area for
pickup.  DO NOT PLACE IN REGULAR TRASH!  Our custodial staff should not
be handling any chemical or other hazardous waste - and this includes
sharps like used razor blades or discarded glass or wafers.

I don't know who did this, and I'll be the first to admit that it's hard
to find who did.  And I'm sure it wasn't intentional.  But we are ALL
responsible for safety in the lab and we ALL need to be aware of not
only our own actions, but those of others working around us.  Therefore,
I am going to inflict penalty on ALL OF YOU...

You have the following choices:

1.  If you have been a labmember for more than one year, you can take
the safety test (again, if you have taken it before).  You can obtain a
safety test from Maureen Baran.


2.  You have to provide me with a question that I can use for the safety
test.  You can email your question to me.  For reference, please review
the safety manual at:

Please do this by Monday, Aug. 23.  If you do not do so, I will
disqualify you from the station(s) you enabled over the weekend.
According to the Coral history, the following people enabled these tools
over the weekend:

headway2:  yinliu, lindaw, weigao, honkai, levi
laurel:  dhum, lgx, arvind, raychen
svgcoat:  kenney, axiu, me342d, crichter, lindaw, weigao, rohank, yeh,
alissa, me342c, mcconnel, jgarate

This is the third egregious incident in two weeks.  I truly don't want
to do impose penalties or threaten, but unless someone can suggest a
better way (and one that does NOT involve installing video cameras!)
then I plan to continue impose punishments on everyone until we see a
change or until Paul Rissman directs us to shut down the litho area.
(Paul warns that he will disqualify everyone from all the lithography
tools, if the situation doesn't change.)

But YOU can make things happen.  Please work safely and make sure
everyone around you works safely.  If you see someone doing something
that makes you feel uncomfortable, SAY something -- if not directly to
them, then to me, or send an email to safety at  Please
spread the word -- Paul's the new sheriff in town and I'm acting deputy
-- unsafe practices will NOT be tolerated.

Thank you for your attention...


Mary X. Tang, Ph.D.
Stanford Nanofabrication Facility
CIS Room 136, Mail Code 4070
Stanford, CA  94305
mtang at

More information about the safety mailing list