What is a pollutant? Jet planes produce chemicals and noise, both types of pollution. Their chemical emissions foul the atmosphere, but what about noise? Produce a rank order of noises, from whispers up to screaming jet engines. What irritates and why? How do pupils' assessments compare with decibel ratings? (for example, quiet room 40 decibels, restaurant 50, conversation 60, street 70, inside car 80, inside lorry 90, electric saw 100, jet engines, pop concerts 120 decibels). Decibels are a logarithmic scale, so each 10 decibels is 10 times noisier than the previous level. Sustained exposure to about 90 decibels upwards harms the ear. What can be done to limit noise? (ear muffs, sound-proofing of machines and rooms, legal restrictions).
Benefits and drawbacks
What are the pluses (quick, convenient) and minuses (air and noise pollution) of jet travel? Are we hypocritical? (oppose pollution, but then travel by plane). What about people who live near airports?
Describe a society (a) without sound (no road drills, but no music or conversation); (b) without jet planes (two or three days to Majorca by land and sea, instead of two hours).
Ted Wragg is professor of education at Exeter University
The Big Picture see page 18