Giant Bubbles

Public summary: 

I'm forever blowing bubbles... but why aren't any of them square? Can you make a square bubble? Come and have a go...

Making giant soap bubbles and looking at how they behave in different shaped frames.
Useful information
Kit List: 

Bubble mixture
Frames with which to make bubbles.
Large container.

Packing Away: 

Wash out container
Rinse and dry frames.


*** OVERVIEW ****

We make giant soap bubbles and look at how they behave in different shaped frames.

Possible activities:
Make bubbles

Other things to talk about:
Surface tension.


Surface tension. This determines the shape of bubbles, causing them to form spheres. When multiple bubbles meet, the shape is again determined by surface tension and not more than 4 bubbles can meet at a point.


The equilibrium between air pressure and surface tension.
The thickness of the film is the same for all bubbles.
Colours in bubbles caused by diffraction.


The bubble mixture we have used before is:
10 parts Cheap washing up liquid
1 part Glycerine/-ol to
100 parts (triply distilled? ) water

You use cheap washing up liquid as there is less random stuff in it which annoys the detergent.

The glycerine increases the viscosity of the liquid, so it runs through the soap film slower, so the film is more stable.

Risk Assessment
Date risk assesment last checked: 
Fri, 31/01/2020
Risk assesment checked by: 
Beatrix Huissoon
Date risk assesment double checked: 
Sun, 02/02/2020
Risk assesment double-checked by: 
Risk Assessment: 

Blowing giant soap bubbles, and looking at how detergent films behave.


Hazard Risk Affected person(s) Likelihood Severity Overall Mitigation Likelihood Severity Overall
Bubble mixture Bubble mixture getting into eyes or being ingested (eye damage/sickness). Public 3 3 9 Try to keep children under control. If the mixture gets into an eye, demonstrator must call a first aider and may perform an eye wash if trained and confident to do so. Similarly alert a first aider if bubble mixture has been ingested. 2 3 6
Spilled bubble mixture Slip hazard. All 5 3 15 Do it outside where surfaces are designed to be wet (e.g. grass), or failing this, perhaps use wet floor signs or similar to let public know that the floor will be wet.
Try to keep the spillages under control, stop the experiment and clear it up if necessary.
Send bubbles towards a designated "unoccupied" spot, where people won't be walking (e.g. towards a table or wall, and perhaps cordon this area off).
Call a first aider in the event if an accident.
2 3 6
Wire frame Wire frames can be pointy and may cause cuts/scrapes/possible damage to eyes. Public 2 3 6 Design the wire frames so all ends are tucked in well. Discourage people from waving the frames around wildly. Call a first aider if required. 1 3 3