Investigating Change Safely
In 2016, Safe Work Australia reported 3,600 chemical-related workplace injuries — nearly all traced back to skipping 1 basic safety step before starting an experiment.
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● Know
- Investigations involving change can include heat, glass, sharps and chemicals — each with its own hazards.
- Safety equipment (goggles, gloves, aprons) and procedures exist for good reasons.
- A risk assessment is the standard first step before any practical work.
● Understand
- Risks come from the substances, the equipment AND the people involved.
- Risk management means anticipating, controlling and responding to harm before it happens.
- School labs follow standard procedures developed from a long history of (sometimes painful) lessons.
● Can do
- Identify hazards in a planned experiment.
- Choose appropriate PPE and safety equipment.
- Write a short safety procedure for a simple change investigation.
Pick up a Bunsen burner and look at it: the barrel has a hole at the base, there is a rubber tube attached, and a gas tap nearby. Every one of those features can cause harm in the wrong hands — a burn, a gas leak, or a flash of unexpected flame. Noticing those possibilities before you turn on the gas is the entire point of lab safety. Before any experiment begins, a scientist must understand the difference between a hazard and a risk. A hazard is anything that can cause harm: hot equipment, corrosive chemicals, broken glass, or open flames. A risk is the chance that the hazard will actually cause harm, taking into account how likely it is and how severe the consequences could be.
A risk assessment is the systematic process of identifying hazards, evaluating the risks they pose, and deciding how to reduce those risks to an acceptable level. It is not about eliminating all danger — that would make science impossible. It is about controlling danger so that learning can happen safely.
A Bunsen burner is a hazard because it produces an open flame hot enough to cause serious burns. The risk of injury is high if you wave your hand through the flame, but low if you tie back your hair, roll up your sleeves, and know how to turn the gas off quickly. The hazard stays the same; the risk changes with behaviour.
At ANSTO, Australia's nuclear science organisation, safety protocols are among the strictest in the world. Every experiment involving radioactive materials requires a detailed risk assessment, multiple layers of shielding, and continuous monitoring. These protocols ensure that cutting-edge research proceeds without endangering workers or the community.
Some students think safety goggles are only for clumsy people who might spill things. This is completely wrong. Goggles protect your eyes from unexpected splashes, flying debris, and fumes that can damage vision permanently. Accidents happen to everyone, including experienced scientists.
Good laboratory practice is built on habits that protect you and everyone around you. Always wear safety goggles when heating chemicals or working with glassware. Tie back long hair, roll up loose sleeves, and wear closed-toe shoes. Never taste, smell directly, or touch chemicals with bare hands. If you need to identify a chemical's odour, waft — gently wave the air toward your nose.
Before using any unfamiliar chemical, read the Material Safety Data Sheet (MSDS) or ask your teacher. Know the location of every piece of safety equipment: the fire extinguisher, fire blanket, eye wash station, and safety shower. In an emergency, seconds count and you cannot afford to search.
A student adds water to a concentrated acid instead of adding acid to water. The reaction releases so much heat instantly that the acid splashes out of the container. Wearing goggles and a lab coat reduces the risk of serious injury, but following the correct procedure prevents the accident entirely.
CSIRO laboratories across Australia require every visitor to complete a mandatory safety induction before entering. These inductions cover emergency procedures, chemical handling, and equipment use. The culture of safety is so embedded that stopping an unsafe experiment is celebrated, not punished.
Many students treat lab coats as decorative accessories or optional fashion. They are not. A lab coat protects your skin and clothing from chemical splashes, hot liquids, and burns. It should be buttoned up and removed before leaving the laboratory to avoid carrying chemicals into public spaces.
Every hazard has a matching control measure, and knowing the pairs can prevent accidents. Hot equipment should be handled with tongs or heat-proof gloves, never with bare hands. A corrosive chemical splash requires immediate rinsing with plenty of water. A small fire on the bench should be smothered with a fire blanket or extinguisher, never waved at. Chemicals in the eyes demand immediate use of the eye wash station for at least fifteen minutes.
Broken glass is a common hazard that is often handled incorrectly. Never use your hands. Always sweep it up with a dustpan and brush, place it in a designated sharps container, and notify your teacher. Small cuts from hidden glass shards can become infected and cause lasting damage.
During a heating experiment, a test tube cracks and hot liquid spills onto the bench. A student who knows the protocol turns off the Bunsen burner immediately, alerts the teacher, and uses a fire blanket if any material catches fire. They do not panic or try to wipe the spill with a paper towel, which could spread the chemical or cause burns.
The Australian Synchrotron maintains a full-time safety team that reviews every experiment before it begins. Their emergency response protocols are practised regularly so that every staff member knows exactly what to do if a chemical spill, fire, or equipment failure occurs.
Students sometimes believe that small amounts of chemicals are safe enough to handle casually. This is dangerous thinking. Even a drop of concentrated acid or a speck of reactive metal can cause serious injury. The quantity does not determine the hazard; the nature of the substance does.
- Hot equipment
- Corrosive chemical splash
- Fire on benchtop
- Chemical in eyes
- Broken glass
- Use dustpan and brush, not hands
- Use fire blanket or extinguisher
- Use eye wash station
- Rinse with water immediately
- Use tongs or heat-proof gloves
Most laboratory accidents are not caused by exotic dangers; they are caused by simple errors repeated so often that they become invisible. Holding a hot test tube by hand instead of using a test tube holder. Pointing the open end of a heated tube toward a classmate. Removing safety goggles because the experiment "looks safe." Each of these decisions turns a manageable hazard into a serious risk.
Another common mistake is heating a closed container. As the liquid inside turns to gas, pressure builds up until the container explodes, spraying hot material in all directions. Always use open or vented equipment when heating, and never seal a vessel that is being heated.
A student heats a chemical in a test tube, holding it in their hand to "get a better angle." The tube cracks from thermal stress, and boiling liquid pours onto their fingers. A test tube holder would have kept their hand safely away from the heat source, and pointing the open end away from people would have protected their face and classmates.
Every Bureau of Meteorology weather balloon launch follows a rigorous risk assessment. Hydrogen gas is highly flammable, so launch teams wear anti-static clothing, ban open flames, and maintain evacuation routes. These protocols prevent accidents in a high-stakes environment where chemistry and meteorology meet.
Many students believe that if they have performed an experiment safely once, they can skip the safety steps next time. Complacency is one of the leading causes of laboratory accidents. Conditions change, equipment wears out, and distractions happen. Safety rules exist because every procedure carries risk every single time.
Here's a student's method. One line has the most dangerous error — click it.
- Hold the test tube in their hand while heating.
- Point the open end toward their face to see the reaction better.
- Do not wear safety goggles because 'it is just a small amount of chemical.'
Great scientists are great risk managers. The scientific method demands careful planning, and that planning must include safety from the very first step. A well-written risk assessment identifies every hazard, evaluates the severity and likelihood of harm, lists specific control measures, and names the person responsible for monitoring safety during the experiment.
Good safety culture is not about fear; it is about respect. Respect for the chemicals you handle, respect for the equipment you use, and respect for the people working alongside you. When every member of a laboratory follows the same standards, everyone can focus on discovery instead of danger.
Before heating copper sulfate solution, a competent student writes: Hazard — hot equipment and boiling liquid. Risk — burns and eye injury. Control — test tube holder, safety goggles, point tube away from people, heat gently. Review — check gas is off and equipment is cool before packing away.
Great Barrier Reef Marine Park Authority dive teams conduct rigorous safety checks before every underwater research mission. Equipment inspections, buddy protocols, and emergency ascent plans mirror the same risk-assessment principles used in chemistry laboratories — because safety is universal, whether you are in a lab or on the reef.
Some students think safety rules are designed to stop fun and creativity. The opposite is true. Proper safety protocols create the freedom to explore, experiment, and push boundaries because you know that the worst outcomes have been anticipated and prevented. A safe laboratory is a productive laboratory.
At the start of this lesson, you thought about how nearly all lab accidents happen because someone skipped just one simple safety step.
After working through the safety procedures for investigating chemical change, which habit do you think you'll need to remind yourself of most? Did anything in this lesson change what you thought was the most important rule?
1. What does a risk assessment help you do?
2. Which piece of equipment protects your eyes during practical work?
3. Why should you use a test tube holder when heating a substance?
4. What should you do before using a chemical you have not used before?
5. When is it safe to remove safety goggles during a practical?