See
https://www.youtube.com/watch?v=B210yttSzcg&feature=youtu.be
https://www.youtube.com/watch?v=iztm_khzHbc
Please watch them and tell us which one you like best. There are:-
1 . The egg.
2. Camping.
3. The talking lady.
We are most grateful to Susan Scotcher of Kingston University for these.
Please send us your comments office@co-gassafety.co.uk