ISO 14001 requires organisations to demonstrate the significance of the identified impacts. By identifying the significant impacts, you can then track back and identify the significant aspects.

You now need to look at the various environmental impacts you have identified and determine the significance of each.

What sort of an impact are they going to make?

And is that impact significant?

The main concern for significance is the capacity to cause harm.

A substance like asbestos is inherently more dangerous than iron dust. Pesticides are more dangerous than food additives. Inert gases like nitrogen are less damaging than carbon dioxide.

When determining the dangerous element significance is based on existing knowledge.

Carbon dioxide a few years ago was ignored as a pollutant until it was found to be a major factor in global warming.