1.2 Working safely
Summary: Have you ever seen the symbols in Figure 1? Sometimes they are at the back of lorries, on labels of cleaning products, or on posters in public spaces. They warn us of dangers and tell us how to work… Tags: science oxford-science student-book-7 Created: 2026-05-19 Last Updated: 2026-05-19
After this topic, you will be able to:
- recognize commonly used hazard symbols and their meanings
- identify possible hazards in practical work
- understand the purpose of a risk assessment.
Think back
- List two ways of staying safe when heating water in a pan.
- Why do most countries have signs to show when there is a sharp bend in the road?
- What is a scientific investigation?
Key idea Scientists need to identify hazards (anything that can harm us) in their investigation and understand how to manage the risks. Common hazard symbols help keep themselves and others safe.
Key words hazard, hazard symbol, risk, control measure, risk assessment
Have you ever seen the symbols in Figure 1**? Sometimes they are at the back of lorries, on labels of cleaning Products, or on posters in public spaces. They warn us of dangers and tell us how to work safely.**
Figure 1Hazard signs show people how to stay safe. Full text alternative to the content
What is a hazard?
A hazard is anything that can harm us or people around us. This could involve chemicals, working on a ladder, using electrical equipment, or working with animals.
Safety is one of the first things scientists must think about before carrying out an experiment. They must think about their own safety and the safety of others.
Katie and Rahim’s experiment involves bouncing tennis balls. In Figure 2, Katie and Rahim discuss the hazards they must think about during their investigation.
Figure 2What are the hazards of bouncing tennis balls?
A State one way Katie and Rahim can carry out the experiment safely.
Hazard symbols
Hazard symbols are placed on product labels, walls, signs, and vehicles. They let us know the danger so we can be safe. Figure 3 shows some common hazard symbols.
Figure 3These are the international hazard symbols and their meanings. Full text alternative to the content
Before 2017, different countries used different hazard symbols. In 2017, all countries agreed to use the same symbols to label dangerous substances and situations. These symbols are called the Globally Harmonized System (GHS).
B Suggest why hazard symbols need to be the same all over the world.
What is a risk?
A risk is the chance that a hazard will cause an injury. Scientists need to think how likely it is that someone will come across the hazard, or how serious the effects of the hazard could be.
You can put a control measure in place to reduce the risk of a hazard causing an injury. A control measure could involve choosing a different method, using safety equipment, or using a less hazardous substance.
Is it safe?
A plan for an experiment should include the steps you will take to stay safe. You will need to wear safety glasses in many scientific investigations. Safety glasses will help to protect your eyes. You should also tie back long hair as it could dip into chemicals, catch fire if using a Bunsen burner, get caught in springs when measuring extension, or distract you by falling into your face.
If you are following someone else’s plan, it will often include a risk assessment. This explains what you must do – or not do – to avoid harming yourself or other people.
C Explain why you should tie back long hair when using a Bunsen burner.
Stretch zone
- Match the symbols to the hazards. Full text alternative to the content Flammable Corrosive Environmental hazard Irritant
- An experiment involves using a flammable chemical. This means it can catch fire easily. The students are wearing safety glasses. State one other control measure that should be in place to protect the students.
Stretch zone
- A student measured 20 cm3 of dilute acid using a glass measuring cylinder. Identify the possible hazards for this part of their method.Suggest control measures for each of these hazards.