Reading comprehension: with the express purpose of… That’s not the express purpose of those planes.

Critical thinking: the express purpose is whatever the creator/operator of the machine says it is.

Jet engines on a plane’s express purpose is to create a high pressure jet of air out one side to propel the craft forward. However, jet engines express purpose can also used to put out oil well fires:

What makes one vs the other? Whatever the creator and operator of the machine decides.

Specifically about geoengineering,

• There is a company releasing sulfur in geoengineering experiments source.

• Spraying sulfur is also used in gardening to treat plant disease and pest control. source

So if I say my “express purpose” of releasing sulfur is for plant disease and pest control, even though the other thing it could do would be geoengineering via the same release, I would be in compliance with the wording of the law yet still be geoengineering.