HIGH SCHOOL SCIENCE LAB EXPLOSION
INJURES 4
A teacher and three Grade 11 girls suffered minor injuries in
a chemical explosion in a science lab at Brennan Catholic
High School in Windsor, Ont., on Tuesday morning. The
explosion, which caused students' ears to ring, was an
exothermic reaction between the ingredients potassium
chlorate, manganese dioxide, sugar and glycerin.
November 23, 2010, reported by CBC news
This is just one of many incidents that have
happened in science labs in recent years
BASIC SAFETY RULES
• Use common sense. If you think what you are about
to do is a bad idea, it is.
• Follow the lab procedure given to you. No
unauthorized experiments.
• No goofing around. See above.
• Handle chemicals and glassware carefully. Use
both hands: one holding the neck of the glassware,
the other hand under the bottom.
CHEMICAL BURNS
Flammable
Health
Reactive
Special
Chemical burns on feet.
This can happen if you
are careless with
chemicals in the lab 
Skin burned by chemicals
SAFETY FEATURES OF THE LAB
Locate the following:
• safety glasses & goggles
• chemical shower station
• fire extinguisher
• eye wash station
• broken glass container
• fire / emergency exit door
DANGER
Laboratory
Safety Rules
NELSON HIGH SCHOOL
Science Department
Safety Rules
1. Read your handout carefully.
2. This sheet must be signed by you and a parent
before you can participate in any lab activities.
PICK OUT 10 UNSAFE THINGS HAPPENING IN THE
FOLLOWING PHOTO
LAB SAFETY SYMBOLS
WHMIS
• stands for Workplace Hazardous Materials Information System
• designed to inform workers about the (dangerous) substances they
use
• aimed at reducing or preventing injuries in the workplace (like school!)
MSDS
• stands for material safety data sheet
• document that tells a scientist about a chemical
• lists hazards, special handling instructions, and risks associated with
a chemical
• are supplied by the company that makes the chemical
• each chemical has its own MSDS that tell about its physical
properties, chemical properties, first aid required, etc.
WHMIS SYMBOLS
can explode if
put under a lot
of pressure
can catch
fire
reacts with air
to increase the
risk of fire
can cause
immediate
illness or death
can cause illness
later in life
(cancer, sterility)
living thing that
can make you
sick
can burn/destroy
the skin & eat
through metals
can react dangerously
if left standing for a
long time, being
shaken, etc.
EXAMPLES OF SUBSTANCES WITH THESE LABELS
Guess as to which substance matches best with which WHMIS symbol:
A. X-ray machines, mercury
B. oxygen cylinder
C. blood, viruses
D. peroxides, nitrates
E. cyanide, arsenic
F. acids, hydroxides
G. ethylene oxide (gas used to sterilize surgical equipment)
H. gasoline
Which WHMIS
symbol should
appear on
cigarette
packages?
PUT YOUR HEADS TOGETHER
1.
2.
3.
4.
5.
6.
7.
8.
A
Compressed Gas
Flammable /Combustible
Oxidizer
Corrosive
(Dangerously) Reactive
Biohazardous (Infectious)
Poisonous
Toxic
B
C
D
In your table
groups, match
up the WHMIS
symbols with
their titles
E
F
G
H
SAFETY SCENARIOS
Discuss what should happen in your table groups:
#1: Sandra
• Sandra heats a test tube filled with acid over the flame
from a Bunsen burner. She then tries to cool the test
tube by running it under cold water. The test tube
breaks resulting in hot acid and broken glass in the sink.
# 2: George
• George is doing a lab activity and decides to not follow
the procedure found in his textbook. He tries mixing two
unknown chemicals together, resulting in bubbles and a
rotten smelling gas. George decides to smell the gas by
holding the beaker directly under his nose. He then
feels nauseous and gets a headache. He leaves the
class and tells no one what he did.
# 3: Cindy & Sam
• Cindy and Samuel are testing the chemical properties of some
various acids and bases. Cindy is goofing around and
accidentally trips Samuel, who is carrying the full beaker of
acid back to his station. The liquid splashes all over Andrew,
who was working quietly next to them. Unfortunately, he was
only wearing his goggles on his forehead (instead of over his
eyes), resulting in acid splashing up into Andrew’s eyes.
# 4: Justin & Corrine
• Justin and Corrine are trying to identify different types of
metals by doing a flame test (where they burn the metal they
identify it by the colour it turns the flame). Justin plays in a
rock band and has really long hair. He leans over to see what
kind of metal is making the bright green flame and
accidentally catches his untied hair on fire in the process.
# 5: Richard
• Richard was late to class on the day of a summative lab. He
hurries into class and tries to catch up to the rest of the
students, only he didn’t pre-read the lab procedure. Richard
ends up making numerous mistakes, like measuring the wrong
amount of chemicals, and falls behind the rest of the class
because he doesn’t know what he is doing. Since this lab is
summative, Richard tries to finish the lab anyway, but gets
different results from the rest of the students.
# 6: Brenda & Nancy
• Brenda and Nancy are sitting in science class together doing
some textbook questions. Brenda decides to pull out her bag of
candy because she’s hungry. Nancy wants to have some too, so
Brenda pours the candy onto the desktop to share. The two girls
then eat their candy, but end up feeling sick to their stomach in
their next class. Little did they know that the class before them
had been doing a lab, testing acids and bases, and did not clean
up properly. Or maybe it was from the biology class from the day
before who dissected their pig right where Brenda and Nancy
were sitting?