Grade by Grade
C. Matter and Energy · Properties of Liquids and Solids

Safety Symbols on Products

C2.7 A1.4About 35 minutes
Learning goals
  • I can explain what the hazard symbols on household products mean.
  • I can tell what the shape around a symbol tells me.
  • I can say what to do when I see a hazard symbol: stop, do not touch, and tell a grown-up.

Words to know

symbol
A picture or sign that stands for something. A symbol can give information without words.
hazard
Something that can hurt you.
poison
Something that can make you very sick or even kill you if you swallow it, lick it or sometimes breathe it in.
flammable
Catches fire easily.
corrosive
Can burn your skin or eyes.
explosive
Can burst or blow apart.
label
The words and pictures on a container that tell what is inside and how to use it safely.

A secret message on the bottle

Look at the bottles under a kitchen sink or in a garage (with a grown-up, and without touching!). Some have small pictures on them, like a flame or a skull and crossbones.

These pictures are safety symbols. They are a message that says: Danger! Stay away! Symbols are used around the world, so people can understand them even if they read a different language.

The pictures inside

On household products in Canada, the picture tells you what kind of danger there is:

  • Skull and crossbones: POISON. It can make you very sick or even kill you if you swallow it or lick it. Some can hurt you if you breathe them in.
  • Flame: FLAMMABLE. It catches fire very easily near heat, sparks or a flame.
  • Hand with liquid dripping on it: CORROSIVE. It can burn your skin and eyes, or your throat if swallowed.
  • Container blowing apart: EXPLOSIVE. The container can burst if it gets hot or gets a hole poked in it. Spray cans have this symbol.
☠️🔥✋💥
Poison, flammable, corrosive and explosive. (These emoji stand for the real symbols, which are black-and-white pictures inside a shape.)

The shape around the picture

The shape around the picture gives more information:

  • An octagon (8 sides, like a stop sign) means the product inside is dangerous.
  • An upside-down triangle (point down, like a yield sign) means the container is dangerous. It could burst.

The label also has a word like DANGER, WARNING or CAUTION. All of these words mean: This is for grown-ups only.

octagon: what is insideis dangerousupside-down triangle:container is dangerous
Left: an octagon like a stop sign, with a flame inside. Right: an upside-down triangle (point down) with a bursting container inside.

Symbols at work and school

In workplaces and schools, you may see different symbols inside a red diamond shape. This system is called WHMIS in Canada, and many countries use the same pictures. Some pictures are the same as the ones at home, like the flame and the skull and crossbones. The rule is the same: stop, don't touch, tell a grown-up.

The 3-step safety rule

When you see a hazard symbol:

  1. STOP. Do not touch, open, smell or taste it.
  2. LEAVE IT. Walk away.
  3. TELL a grown-up right away.
Riddle time

What has 8 sides and is very good at saying STOP?

An octagon! On the road it is a stop sign. On a bottle it means: stop, leave it, tell a grown-up.

Worked example

Let's read a label

A grown-up holds up a bottle of oven cleaner. It has a black octagon with a hand and dripping liquid inside, and the word DANGER. What does it tell us?

  1. Look at the shape: It is an octagon like a stop sign. That means the product inside is dangerous.
  2. Look at the picture: A hand with liquid dripping on it. That means corrosive: it can burn skin and eyes.
  3. Read the word: DANGER. This is for grown-ups only.
  4. What should I do? Stop, leave it, and tell a grown-up if I find it somewhere it should not be.

The oven cleaner is corrosive: it can burn skin and eyes. Only a grown-up should use it, following the label.

Worked example

Let's think: Why is there an upside-down triangle on a spray can?

A can of spray paint has an upside-down triangle (point down) with a picture of a container blowing apart. What does it mean?

  1. Shape: An upside-down triangle means the container is dangerous.
  2. Picture: A container blowing apart means explosive.
  3. Why? Spray cans are full of stuff under pressure. If the can gets hot (near a heater or in a hot car) or gets poked with a hole, it could burst.
  4. Safe choice: Keep spray cans away from heat and never poke them.

The can could burst if heated or poked. Keep it away from heat, and let grown-ups handle it.

Hands-on activity

Symbol detective

You need: paper, crayons, and a grown-up.

  1. A grown-up collects 3 or 4 products with hazard symbols (for example, a cleaner, a spray can, windshield washer fluid). The grown-up holds them. You only look.
  2. Find the symbol on each one. What is the shape? What is the picture? What is the word (DANGER, WARNING or CAUTION)?
  3. Draw each symbol and write what it means: poison, flammable, corrosive or explosive.
  4. Make a "STOP! Ask a grown-up" poster with the symbols. Hang it where younger brothers and sisters can see it.
  5. The grown-up puts the products back in a safe, high or locked place.

Talk about it: Why do products use pictures and not just words?

Your turn

1

What does a skull and crossbones mean?

2

What does a flame symbol mean?

3

What does the corrosive symbol warn you about?

4

What does an octagon around a symbol tell you?

5

What does an upside-down triangle around a symbol tell you?

6

What are the 3 steps when you see a hazard symbol?

7

Why are symbols helpful?

More practice: warm-up

1

What shape is a stop sign?

2

Should you smell a bottle with a skull and crossbones?

3

Does a flame symbol mean it catches fire easily?

4

Who should use products with hazard symbols?

5

What should you do if you find a cleaner bottle on the floor?

More practice: on your own

1

A bottle has an octagon with a skull and crossbones and the word WARNING. What does that mean?

2

Why should spray cans never go near a heater?

3

Your little cousin picks up a bottle with a flame symbol. What should you do?

4

What is WHMIS?

5

Why do labels also have words like DANGER, WARNING or CAUTION?

Challenge

1

Some products have two symbols, like flame and explosive on a spray can. What does that tell you?

2

A younger child cannot read yet. How do safety symbols help keep them safe?

3

Design your own symbol for "very hot, do not touch". Describe it.

Check your understanding

Quiz

1.

What does the skull and crossbones symbol mean?

2.

A flame symbol means the product...

3.

An octagon shape around the picture means...

4.

Which symbol would be on a spray can, warning it could burst?

5.

You find a bottle with a hazard symbol. What should you do first?

6.

The corrosive symbol warns that a product can...

For parents and teachers

Big idea: Hazard symbols give safety information without words (C2.7). On Canadian household products, the picture names the hazard (poison, flammable, corrosive, explosive) and the frame tells you whether the contents (octagon) or the container (upside-down triangle, point down) is dangerous. Signal words such as DANGER, WARNING or CAUTION also appear. Workplaces and schools use WHMIS pictograms in red diamonds.

How to help: Do the symbol detective activity with you holding the products. Practise the rule "Stop, leave it, tell a grown-up." This is a good time to check that hazardous products are stored up high or locked away.

Common difficulties:

  • Thinking the symbol means "a little bit dangerous". Every hazard symbol means grown-ups only.
  • Mixing up the corrosive and poison pictures. Corrosive = burns skin; poison = harmful if swallowed.

Safety: Children should never handle products with hazard symbols, even to read the label. Keep your local poison centre's number in your phone. In an emergency, call 911.