Accidents Happen

1
Safety Matters Real Life Scenarios
Accidents Happen
Safety Workshop TCD
April 2006
2
Chemical Hygiene

• Skin contact
• Accidental stabbing, cuts, other skin breaks,
  entry
• into deep tissues, bloodstream
• Local Toxicity / effect (dermatitis, cracking of
  skin)
• Penetration through skin - dimethyl sulfoxide,
  alcohols, benzene, carbon disufide pass through
  epidermis and act as a vehicle.

3

• Inhalation
• Splash, dust particles, gas,
• caustic vapours
• Queens University Belfast, Pharmacy Lab
  evacuated for 24 hours following Br spill
  poisonous, deep oily liquid causing burns
• Ingestion (object-to-mouth)
• Contamination, deposition on surfaces, foods,
  smoking, nail-biting

4
Protective Clothing
Hands cuts, sores forearm hair folicles eyes
- toluene
Graduate student severly burnt from waist down
dropped a beaker of ether onto a heated surface
which caused a flash explosion beneath a chemical
fumehood hospitalised for 2 weeks
5
Chemistry Professor Karen E. Wetterhahn,
Dartmouth College
Died by poisoning resulting from by a few drops
of dimethylmercury.
Dimethylmercury, a colourless liquid, was used as
a reference standard for NMR experiments.
During sample preparation dimethylmercury
accidentally penetrated a protective glove.
The accident occurred in August of 1996. Six
months later symptoms of the mercury poisoning
were detected by which time the effects were
irreversible. Professor Wetterhahn rapidly went
into a coma and died in June 1997.
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Protective Gloves
During the investigation of this accident, it
was learned the MSDS prepared for both the
manufacturer and supplier of the dimethylmercury
sample in question had erroneous information on
the proper gloves to be worn when handling this
extremely toxic compound". This is a tragic
example of what can happen when MSDS information
is incorrect. As a result of her tragedy, safety
standards for gloves and other protective
equipment were revised, and a movement began to
eliminate production and use of dimethylmercury.
At the time of her diagnosis and before she
lapsed into a vegetative state, Prof. Wetterhahn
asked that her case be made known to others in
the hope of preventing a similar tragedy.
Applied Occupational and Environmental Hygiene
Volume 16(2) 233236, 2001
7
Laboratory Environment The scene of an accident
8
University of Kentucky 1997
Chemical wastes accidentally mixed resulting in a
fire and explosion





Choloroform added to the waste bottle resulted in
Brown Fumes. The bottle was capped and the
student and walked away. A minute or two later
it exploded

The explosion blew glass shrapnel across the
laboratory and was immediately followed by a fire
that engulfed the lab giving-off thick black
smoke
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Accident University of Kentucky 1997
The Debri

• Burn marks and soot above the hood
• Overhead fluorescent lights shattered by flying
  debris.
• Glass fragments from the explosion travelled up
  to 10 metres
• Some embedded up to 20 mm deep in the fumehood
  insulation

Remember The Fume Hood is not a Storage
Area This accident occurred in a hood that
contained many stored chemicals as well as waste.

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Sonicator Causes Explosion Univeristy of
Ohio What Happened A graduate student used a
sonicator to agitate a mixture of zinc, ethyl
ether, and bromoethylacetate (a lachrymator) in a
sealed round-bottom flask. The sonicator caused
a rapid rise in temperature which sent the
contents of the flask into the fume hood. A
graduate, was exposed to the lachrymator vapours,
causing intense irritation to the eyes and lungs.

What can be done to prevent this from occurring
again? Sonicators use sound waves to agitate
mixtures...this can cause rapid heating and
localized points of increased pressure. They
should not be used with sealed flasks or with
flammable liquids...especially low-boiling
solvents (such as ether). The sonicator was in
the fume hood, but it was placed in the front
just behind the sash. The equipment should be set
as far back as possible...away from the sash.
The student was not wearing eye protection.
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Working In Fume hoods

• If a hood is being used to store particular
• chemicals then run the reaction in a different
• hood.

2. Keep the Sash at the appropriate Level.
When not in use, the sash should be closed.
When you are using the hood, the sash should be
no higher than 14 inches. If higher than, then
fumes are escaping into the room and hence into
your lungs.
3. Keep all work gt15 cm behind sash opening
4. CLEAN UP! Remove all equipment and chemicals
that you brought into the hood. Place all
reagents back in their proper storage place.
Dispose of all waste.

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Working In Fume hoods
5. Unattended Reactions All unattended
reactions must be known about - labelled with a
description of the reagents/hazards and contact
details
In 1997 a fire destroyed a research laboratory at
the University of Washington, estimated damage
500,000 and wiping out several research
projects. The fire, started by an unattended
hotplate, began in a laboratory on the top story
of five-story research facility. Fire department
officials said the fire was contained largely in
one room but was intensely hot. No one was
injured.
Safe Science May 1997
13

• Specific Procedures
• Solvent Wastes
• Storage chemical turn-around
• Distillation destroying the evidence

14


Sodium in the distillation of solvents
15
Fire at UT Austin Chemistry Laboratory On
October 19, 1996, a fire broke out in an
organic-synthetic chemistry lab.  The fire
began when a post-doctoral researcher was
disposing of some sodium metal.  The researcher
was in the process of deactivating the sodium by
exposing the metal to alcohol.  A small amount of
residual metal, came into contact with water as
he poured the material down the sink creating a
small flame. The fire grew into a blaze when the
researcher accidentally broke a container of
acetone into the sink in an attempt to remove the
container from the sink area where it was being
stored. The principal investigator characterized
the laboratory as a total loss (0.5 million
dollars of damage).  Many research records and
notes for current projects were destroyed, as
well as a lot of archival material going back 10
to 15 years.  In addition, two adjacent
laboratories were heavily damaged by smoke and
water. The Austin Fire Department primarily
blamed the incident on poor housekeeping of
chemicals.  Chemical inventories for the
laboratory were kept electronically and the
responding fire fighters had no information on
what chemicals were involved in the fire.  As a
result, unlabelled containers and improperly
stored flammable chemicals were encountered
during the fire fighting effort. 
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• Real-life Events have Highlighted
• Chemical storage, turn-around
• - Keeping accurate risk assessment
• Personnel saftey equipment
• Wear appropriate protection
• Correct fumehood use
• Close the sash, keep clear, keep equipment to
  the back
• Chemical waste disposal
• Do not mix wastes
• metal residues, caustic residues, chlorinated
  solvents