>Has anyone encountered accidents involving glass pressure tubes which
>were commonly used for organic synthesis in research labs? One example
>of this can be found from Ace glassware
>http://www.aceglass.com/html/2008/html/index_html.php?page=714
>
>We recently had an accident involving such a pressure tube which was
>used for an organic reaction involving phenylmalemide, triphenylphospine
>and para-formaldehyde in 3.4ml acetic acid, injuring 2 students who are
>working in front of the fumehood. We are still investigating the
>accident but initial assessment points to lack of hazard analysis as
>well as other safety lapses.
>
>
>Regards
>Khaiseng
>Department of Chemistry
>National University of Singapore
>khaiseng**At_Symbol_Here**nus.edu.sg

Formaldehyde can thermally decompose into methanol and carbon 
monoxide, the danger increasing with temperature.

All reactions involving glass bombs should be performed in a fume 
hood *and* behind a safety shield.

Whe I was a chemistry professor, I witnessed the aftermath of two 
such incidents.  The analysis of the first one is long, so I will 
detail the second one in a second email.

This account of the first incident is a slightly abridged version of 
a rather lengthy letter I wrote to various university officials on 
the date of the incident, October 17, 1995.  I've changed some 
wording to remove names etc.    This accident was the result of 
heating a 25-50 mL sealed glass bomb with, if I recall correctly, 
methylene chloride.  While the incident was rather minor, it could 
have been much worse; as you read, you will see that it was a useful 
learning experience:

Note: as you read about the fire department "response" keep in mind 
that when I came out of the building, there were 14 pieces of fire 
equipment and a command post waiting....hence my frustration that is 
evident.   I'm happy to say that as a result of this incident, our 
understanding of how to liaison with the local fire department 
improved greatly and that we had a good rapport with their commander 
after this.  And the fire alarm system was finally upgraded as well.

---

Having spoken with the students who were working in the vicinity of 
room 47 and based on my own personal experience, I present my best 
analysis of the events that occurred earlier today.  I follow this 
statement with a list of recommendations and a serious protest about 
the manner in which the fire department's Incident Commander 
responded to this situation.

Earlier today an explosion was heard by students working in the 
[adjacent laboratories] and by those in the hallway at the time.  An 
undergraduate geology student told me that a "huge fireball" shot out 
from underneath the closed door of the laboratory when the explosion 
occurred.  A graduate student working next door [to the left side of 
room 47] at the time reports that the explosion was powerful enough 
to cause the cabinet doors on the right side of his room to swing 
open.  A graduate student who was standing outside of [a lab 2 doors 
down on the right] at the time also heard the explosion.

Both graduate students raced to the room 47.  They found the door 
closed and detected neither flame, smoke nor heat emanating from the 
room.  They attempted to open the door to investigate further but the 
door was locked and they do not have keys to room 47.  As laboratory 
personnel are not permitted to work in locked laboratories it seemed 
unlikely to them that there might be injured workers inside the 
laboratory and they further decided that breaking the window to the 
enter the room might aggravate a bad situation if the room was, in 
fact, on fire.

As neither student yet had confirmation that there was an emergency 
situation inside the room, one student ran to inform the professor 
assigned to the lab (office upstairs) and the other ran to my office 
(the closest faculty office).  The student who came to my office 
stated "there's been some kind of explosion or fire in room 47".  I 
was on the phone talking to a colleague, but simply hung up in 
mid-conversation and sprinted down the hallway to room 47.

Upon arriving at room 47 I could not detect heat, smoke or flame.  I 
felt the door and window (which was covered from the inside with 
white paper, thereby blocking our view of the interior) and found 
them cool to the touch.  I unlocked the door and cautiously cracked 
it open as I stood to one side.  I was aware of the potential for a 
backdraft situation, but knowing that the room has a recently 
upgraded high capacity air handling system it seemed unlikely that 
any fire present inside could have been oxygen-deprived.  As I opened 
the door I could see that thick gray-white smoke filled most of the 
room except for the area near the door and fume hoods which was 
clear.  Again using extreme caution, I peered around the door and saw 
that the equipment and materials inside the right fume hood were on 
fire.  I also noted that the sash on the fume hood was open all the 
way and that there was a 1 gallon organic waste bottle being singed 
by the flames.  While I recognized that this was actually a rather 
small and well-contained fire, I realized that if this waste bottle 
were to explode a more serious situation could ensue [an 
undergraduate laboratory class was in session across the hallway].

Therefore, in full accordance with University procedure, I backed out 
of the room, closed the door, and told one student to call 911.  I 
yelled to the undergraduate laboratory manager to pull the fire alarm 
and evacuate the building.  I then ran to room 45, grabbed a CO2 fire 
extinguisher and told the other personnel in the hallway to fetch 
additional fire extinguishers.  I then cautiously reopened the door 
to room 47 and because the door opened into the lab (to my right) I 
was able to aim the fire extinguisher at the fire without exposing 
myself to the fire or other such peril.  Still standing behind the 
door, I swept the hood with the fire extinguisher and succeeded in 
putting out all but a few small flames.  I then used an additional 
extinguisher to finish putting out the fire and then used a third one 
for good measure.  We pulled the pin on a fourth extinguisher, but 
did not need to use it.

We waited several minutes to ensure that the fire would not reignite 
and then, with coworkers standing by with fire extinguishers, I 
removed the undamaged solvent bottle from the hood and unplugged the 
electrical equipment that was inside the hood.  As there were no 
standing puddles of solvent in the hood or on the floor and we had 
removed the only remaining flammable materials from the hood it 
seemed that the possibility of reignition was minimal.

Shortly after the fire was extinguished [my department chair and the 
professor assigned to the laboratory] arrived on the scene.  After I 
fully informed them of the events that had transpired and after 
discussing with [the professor] what equipment and materials were 
involved it was plainly obvious to all of us that there was no 
further danger posed by this situation.  They both then went outside 
to meet with the fire officials who had now arrived at the building 
but had not yet entered.

Expecting that a fire crew would shortly arrive at room 47, realizing 
that they would need a professional on hand to appraise them of the 
situation to detail possible health or safety risks and being 
absolutely certain that there was no danger, I remained in the 
hallway outside of room 47 with a graduate student present as a 
"backup" in the extremely unlikely event that something else did 
happen.  We waited patiently for several minutes without seeing a 
single fireman.  We walked to the rear door of the building and saw 
no firemen, although we encountered several students who were only 
now leaving the building.  I angrily yelled at them "What the hell do 
you think that alarm means...get out of the building NOW".  One of 
them asked rather derisively "what's your problem?"  I replied that 
my problem was that unless they wanted to be arrested they had better 
leave.

Still not encountering firemen and having no idea what building 
entrance they would come through, the student and I returned to the 
hallway outside of 47 to wait for the fire crew.  After about 10 
additional minutes, some sort of announcement was made over the fire 
alarm PA system which said something about "evacuate now".  Assuming 
that the firemen were now on their way into the building we remained 
on scene for another three or four minutes, but when none arrived we 
exited the building through the rear doors.

There I met up with the Incident Commander.  I explained to him what 
had happened, that the fire was out for some time and that the smoke 
had cleared the room.  I tried to detail in the simplest terms 
possible that not only were there no teratogenic, carcinogenic or 
mutagenic substances involved but that there was only the most 
extremely remote chance that the fire could reoccur or that toxic 
vapors were present.  I told him the only equipment that would be 
needed by anyone entering the laboratory would be gloves  (if they 
would be handling materials) and eye protection (as is required for 
all laboratory visitors).  I then talked to several university safety 
officials.  I gave details of the incident to [deleted] who handled 
the media swarm that had by then assembled in the parking lot.

After our initial contact with the Incident Commander we stood 
outside waiting.  I recall hearing one of the firefighters  remark 
that they were "waiting for the air to clear out in there before we 
go in."  After another 10 or so minutes had elapsed University 
personnel, not firefighters, were sent into the building wearing 
Tyvek bodysuits and full-face respirators.

I need to make several very important points about this incident.

*  I must voice my strongest possible concern that the firefighters 
did absolutely nothing to make a firsthand assessment of the 
situation in room 47 or even enter the building for at least 20 
minutes from the time the fire was called in.  I have witnessed 
several major lab accidents at other universities, accidents many 
times worse than the minor one we had today, and  can confidently 
state that the response to today's incident was by far the most 
abysmal.  During accidents at MIT and Cornell we had public safety or 
fire personnel on scene in less than 3 minutes.  If today's minor lab 
fire had not been contained or there had been injured people inside 
this building it is quite likely that the fire would have done 
widespread damage and in the process killed or injured occupants 
and/or firefighters.  Why did the fire crews abrogate their 
responsibilities of ensuring public safety by refusing to enter our 
building for so long?  This is an intolerable situation and I fear 
that in a future accident the hesitant, paranoid, chemophobic 
response displayed today will result in a serious injury or death 
that could have otherwise been avoided.  Are we supposed to put out 
all our own fires from now on?  How long would they have waited and 
what damage would have been done if we had not controlled the 
situation?  Are they going to listen to our advice when we tell them 
there is or is not a danger?

*  [Many people] witnessed me make a clear, coherent, concise and 
informed report to the Incident Commander whose response was a rude, 
insulting, derogatory and holier-than-thou tongue-lashing about my 
remaining in the building after the fire alarm (which I had ordered 
pulled) went off.  I got to hear how my allegedly irresponsible 
action could result in him "having to send my men in to get you out" 
and endanger their lives.  Obviously, if I had thought there was even 
the smallest amount of danger I would have left the scene 
immediately.  If I had any reason to believe that toxic fumes were 
present (recall that we had already confirmed that they were not) I 
would not have remained.  Quite simply, I am not a child, a yahoo or 
a fireman wannabe, but a trained chemical professional with a greater 
knowledge of the scene than the Incident Commander himself.  I 
recognize and fully appreciate his concerns, but for him to act in 
such a belittling manner when I had the best knowledge and 
understanding of the situation is not only rude and insulting but 
irresponsible and unprofessional.  To be honest, I resisted the urge 
to tell him what I thought of his attitude, but instead elected to 
maintain my professional demeanor.  I later approached him, again in 
a professional manner, and inquired about what we can do in the 
future to facilitate communication at future incidents; I will be 
happy to discuss this at our next faculty meeting.  Let me say for 
now that I have a great problem with his suggestion that I run around 
outside the building (which you will recall has six widely separated 
entrances) looking for the Incident Commander when we had already 
told the police dispatcher where to find the on-site contact.   Let 
me also point out that I found the other members of the fire crew to 
be courteous and professional, unlike the Incident Commander.

*  As always in our building, there were many occupants who did not 
hear the fire alarm.  [2 people] came out of the NMR lab (directly 
across the hall from 47) about 10 minutes after the fire was out and, 
not because they had heard the alarm (they hadn't) but because they 
were on their way to lunch.  Students in room 20 have this problem 
all the time; with the doors closed they can not hear the fire alarm 
over the sound of the vacuum pumps in the laboratory.  I was told by 
a student that the alarm was not heard in the Chemistry-Physics 
Library which is located one floor above the scene of this incident 
and which lacks emergency exits.  Additional sirens need to be 
installed in this building and a comprehensive survey of those rooms 
without sirens should be conducted immediately.

*  Other students heard the alarm but chose to ignore it (see my 
account above).  Many other departments use the classrooms in our 
building and it is obvious that some of these outside faculty and 
students do not have a good grasp of what dangers a fire, 
particularly one in a laboratory building, pose.  False alarms are 
quite common in our building and this has led to a tendency to ignore 
them.  We need to make sure that all persons teaching classes in this 
(or any) building evacuate classrooms and laboratories as soon as the 
fire alarm is heard.  I specifically suggest that Chemistry faculty 
members be asked to check classrooms and laboratories when a fire 
alarm is sounded and force recalcitrant students and faculty to 
evacuate.

*  I want to commend [several people] for their prompt and 
professional response to this situation.  There were several people 
from Physical Plant who were also were involved although I do not 
know their names.  The TA's who were teaching the undergraduate 
laboratory in the basement level should also be commended for getting 
their students out of the building in a prompt and controlled manner.

*  When I called the Fire Safety office to have the used 
extinguishers replaced, I requested 10 pound instead of 5 pound CO2 
extinguishers.  It should not take more than one extinguisher to 
quench a simple solvent fire in a fume hood (something I have done at 
least five times at other universities).  It may be worthwhile for 
other faculty members to consider upgrading their extinguisher 
capacities.

*  This incident clearly shows the danger of having student desks 
inside the laboratory, particularly for first year graduate students 
who are not assigned to research groups and do not have a full 
understanding of the dangers that may exist.  Every effort must be 
made to provide outside space for graduate student desks, perhaps by 
converting a few of the smaller classrooms to offices.  In addition, 
I believe it should be departmental policy that TA's not be permitted 
to tutor students in laboratories, a policy that I enforce in my 
research group.

I am sure that [the professor who occupies the lab] will be giving 
you a full assessment of the today's events and the chemicals 
involved.  On the basis of information available to me I can make 
three specific comments regarding the safety practices in room 47.

1)   If the window of the door to room 47 had not been covered, the 
graduate students would have been able to ascertain whether injuries 
were involved and whether a fire was in progress.  I recommend that 
all laboratories, except for those requiring the exclusion of ambient 
light for scientific experiments, be required to have windows that 
permit a clear view of the interior.  While this is bad from a crime 
prevention standpoint, safety should be our paramount concern.  I 
have already consulted with [the professor] on this matter and we 
have removed the window coverings in his laboratories.

2)   The hood sash was fully open when the explosion occurred.  As 
the experimenter was heating a solvent above its boiling point in a 
sealed vessel (a routine practice that poses no unusual hazard), a 
safety shield should have been around the vessel and the hood sash 
should have been lowered.  Oddly, it appears that had the hood sash 
been closed in this particular situation, the accident would not have 
been minor because the containment of the fire would have ignited the 
remaining solvent bottle.  Furthermore, had the hood sash been fully 
closed I would not have been able to easily extinguish the fire and 
the hood would have been damaged from the contained heat.  However, I 
consider this case unusual because there were no workers present in 
the lab.  Had personnel been present, serious injury would likely 
have occurred, and I therefore recommend in the strongest possible 
terms that we vigorously enforce policies mandating that all fume 
hood sashes be kept closed when experiments are in progress.

3)   A contributing factor to this incident was the storage of 
solvent/waste bottles in the hood.  My best guess, and this is only a 
guess, is that the reaction vessel developed a flaw and burst.  The 
resulting glass fragments then broke one of the two solvent bottles 
in the hood, releasing several hundred milliliters of liquid on the 
floor of the lab and hood.  When this solvent reached the hot plate a 
flash fire occurred, generating the fireball and "explosion" which is 
more correctly described as a deflagration (the concomitant 
shattering of a vacuum Dewar flask would have made this sound like an 
explosion).  We could find no evidence that this flash singed 
anything outside of the hood, but by examining the spray pattern of 
mineral oil and glass fragments on the floor of the lab it is clear 
that material was forcefully ejected from the hood.  A second 
possibility is that the hot plate used to heat the mineral oil bath 
malfunctioned and raised the oil above its flash point.  A third 
possibility is that the waste/solvent bottles were too close to the 
hot plate and either cracked or built up enough pressure to burst. 
Regardless of which of these scenarios is correct, it is certain that 
at least one solvent bottle was involved in this fire.  I therefore 
recommend that we review and enforce our policies about storage of 
solvents or waste bottles in fume hoods.

My last recommendation is that when the local fire departments come 
through the building on their semiannual inspections/tours that they 
talk to faculty members and laboratory workers to fully understand 
the relative risks involved in these situations.  Fire crews should 
be shown the possible hazards they might run into and be able to ask 
questions about appropriate responses.  We must work to eliminate the 
chemophobic apprehension that we witnessed today and ensure that the 
fire department is our partner in guaranteeing the safety of both our 
organizations.

Let me finish by stating once again that this was a relatively minor 
incident which produced little damage (the hood involved was 
undamaged and is ready for use).  Thanks to the prompt and 
professional response by our students and staff this incident did not 
evolve into a larger problem.  I look forward to working with you and 
other University officials to learn from this experience and 
institute policies that will prevent accidents of this nature from 
happening again.

Rob Toreki
-- 
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