Before You Start: Test Tube Safety Checklist

• Wear safety goggles and any PPE required by your laboratory, school or risk assessment.
• Check every test tube for chips, cracks, scratches, sharp edges or clouding before use.
• Never use damaged glassware, especially if the tube will be heated.
• Choose the correct size, material and wall thickness for the activity.
• Use a test tube rack when tubes are not being held.
• Label tubes clearly when comparing samples or running multiple tests.
• Check whether the tube is suitable for heating before using it with a Bunsen burner, hot water bath or other heat source.
• Keep test tubes away from bench edges and avoid leaving them loose on the work surface.
• Follow your laboratory’s chemical handling and disposal procedures.

Parts of a Test Tube and Their Functions

Understanding the basic features of a test tube helps users choose the correct tube, handle it safely and avoid common problems such as chipping, rolling, overheating and contamination.

Test Tube Terminology Explained

These terms are useful when choosing laboratory test tubes, following practical instructions or comparing glassware and accessories.

Choosing the Right Test Tube

Choosing the correct test tube depends on the activity, sample type, volume, heating method and safety requirements. The wrong tube can increase the risk of breakage, contamination or poor results.

Heating Test Tubes Safely

Heating test tubes is common in school chemistry and laboratory demonstrations, but it is also one of the highest-risk test tube activities. Heat-resistant glassware, correct technique and supervision are essential.

1. Use a suitable heat-resistant test tube.
   Check the tube is designed for heating and is free from damage.
2. Fill only to a safe level.
   As a general classroom rule, fill no more than one-third full unless the practical instructions say otherwise.
3. Hold the tube with a test tube holder.
   Grip near the upper part of the tube so your hand remains away from the heat source.
4. Point the opening away from people.
   Never point the mouth of a test tube towards yourself, another person or a walkway.
5. Heat gently and evenly.
   Move the tube through the flame or heat source rather than heating one fixed spot.
6. Watch for boiling, splashing or colour change.
   Stop heating if the reaction becomes too vigorous or the liquid begins to bump or spit.
7. Allow the tube to cool safely.
   Place it in a rack or on a heat-safe surface and assume it is hot until confirmed otherwise.

How to Hold, Move and Transport Test Tubes

Can You Measure Liquids in a Test Tube?

Some test tubes include graduation marks, but these should usually be treated as approximate guides only. Test tubes are not designed for accurate measuring in the same way as measuring cylinders, volumetric flasks, pipettes or burettes.

Cleaning Test Tubes Correctly

Good cleaning prevents contamination, reduces staining and helps test tubes remain clear and reliable for future practical work.

1. Empty contents safely.
   Follow the approved disposal route for chemicals, biological samples or contaminated liquids.
2. Rinse as soon as possible.
   Prompt rinsing helps prevent residues drying onto the glass.
3. Wash with suitable detergent.
   Use warm water and a laboratory-approved cleaning method.
4. Use a test tube brush if required.
   Brush gently to remove residue without scratching or weakening the glass.
5. Rinse thoroughly.
   Remove detergent, cleaning solution and loosened residue.
6. Check clarity.
   Look for remaining marks, cracks, staining or clouding.
7. Dry upside down.
   Use a test tube drying rack so water can drain and air can circulate.

Storage and Organisation

Correct storage helps reduce breakages, saves preparation time and keeps test tubes clean for future use.

• Store clean, dry test tubes in suitable racks, trays or labelled containers.
• Separate tubes by size, material or purpose where possible.
• Keep glass test tubes away from bench edges and busy walkways.
• Avoid overcrowding racks or storage containers.
• Do not store damaged tubes for later use.
• Keep plastic and glass tubes separate if they are used for different applications.
• Inspect stored tubes regularly and remove chipped, cracked or stained glassware.
• Store compatible accessories nearby, such as stoppers, holders, racks and brushes.

Common School Science Activities Using Test Tubes

Test tubes are widely used in KS3, GCSE, A Level and general laboratory practical work because they are compact, easy to compare and suitable for small-scale reactions.

Equipment Commonly Used With Test Tubes

Using the right accessories improves safety, organisation, cleaning and classroom efficiency. The products below are commonly used alongside test tubes in schools, colleges, universities and laboratories.

Common Test Tube Mistakes and How to Avoid Them

Test Tube Troubleshooting Guide

Emergency Actions for Test Tube Incidents

Always follow your laboratory’s emergency procedures and inform the teacher, technician, supervisor or first aider immediately where required.

Test Tube FAQs

What are test tubes used for?

Test tubes are used for holding, mixing, heating and observing small amounts of liquids, solids or samples during science experiments and laboratory work.

Can all test tubes be heated?

No. Only use test tubes that are suitable for heating. Borosilicate glass test tubes are commonly used for heating, but users should always check the product specification and laboratory instructions.

What is the difference between a test tube and a boiling tube?

A boiling tube is usually larger than a standard test tube and is often used when heating larger volumes or when extra space is needed to reduce the risk of boiling over.

How full should a test tube be when heating?

For many school practicals, a test tube should be no more than one-third full when heated unless the instructions say otherwise. This helps reduce splashing and boiling over.

Why should you point a heated test tube away from people?

Hot liquid, vapour or reacting chemicals can sometimes eject from the tube. Pointing the opening away from people reduces the risk of injury.

Can test tubes be used for accurate measuring?

Graduated test tubes can be used for approximate volume estimates, but they should not be used for accurate measuring. Use measuring cylinders, pipettes, burettes or volumetric glassware when accuracy matters.

How do you clean a test tube?

Empty it safely, rinse promptly, wash with a suitable detergent, use a test tube brush if needed, rinse thoroughly and dry upside down in a rack.

How should test tubes be stored?

Store test tubes clean and dry in suitable racks, trays or labelled containers. Separate by size or material where possible and remove any damaged glassware.

What should I do if a test tube breaks?

Do not pick up broken glass with bare hands. Keep others away, follow your laboratory’s procedure and dispose of the glass in an approved glass waste container.

Need Test Tubes, Racks or Laboratory Glassware?

Now that you understand how to use test tubes safely, choosing the correct equipment is the next step. The right tube material, size and accessories can improve safety, reduce breakages and make practical science lessons easier to manage.

Better Equipped supplies test tubes, boiling tubes, racks, holders, brushes, stoppers, safety equipment and laboratory glassware for schools, colleges and laboratories throughout the UK.

About This Guide

This guide was written and reviewed by Better Equipped's technical team, drawing on experience supplying test tubes, boiling tubes, laboratory glassware, racks, holders, brushes and practical science equipment to schools, colleges, universities and laboratories throughout the UK.

Our aim is to help users improve laboratory safety, reduce glassware breakages, support practical science teaching and get the best possible results from everyday science equipment.

Last reviewed and updated: June 2026